Error F21 (E21) in Bosch and Siemens washing machines

When starting the Bosch washing machine, the drum does not rotate; the display shows error F 21. Let's look at what this means.

The drum may also stop mid-wash.

Electromechanical BOSCH CM models display an error by flashing (lighting) the speed (1000-800, 800-600) and rinse lights.

Note! Error code F21 for a Bosch washing machine is critical. You need to immediately turn off the power to the machine.

Description

When using Bosch equipment, error F21 may appear not only in the form of a code of letters and numbers. On Bosch models that do not contain a display, the fault is indicated by a combination of flashing indicators located on the control panel.

Flashing indicators allow you to recognize a number of errors. Technicians who have extensive experience working with similar washing machines determine error code F21 offhand. But an ordinary user can also identify an error using indicators. To do this you will need a table of error codes.

On Bosch washing machines without a display, error F21 is displayed as follows. The washing machine freezes and does not respond to button presses. Also, the machine does not respond to turns of the program selector. At this moment, 3 lights on the control panel flash or light up at once: rinse, 800 revolutions and 1000 revolutions.

You can see how the F21 code is displayed on Bosch machines without a display in the picture below.

Older models spin at a maximum of 800 rpm. In this case, the rinse, 600 and 800 rpm indicators will light up.

Code F21 has a fairly simple interpretation. However, this does not mean that determining the causes of its occurrence will be easy.

Code F21 indicates that the drum does not rotate in Bosch equipment. Before displaying code F21 on the control panel, the Bosch washing machine attempts to start the drum. And if this fails, then the corresponding code F21 appears.

This error may appear if the following malfunctions occur:

• tachometer failure. With this malfunction, information about the speed of the washing machine motor is not sent to the control module. As a result, it stops the Bosch machine from working, and then displays error code F21,
• engine malfunction. A broken motor cannot rotate the drum. Therefore, after several unsuccessful attempts to start the engine, the module displays error F21,
• The circuit supplying the tachometer or motor has broken. This malfunction occurs when the wiring is broken or the contacts are oxidized. The motor and sensor are in good condition,
• During the washing process, a foreign object may enter the tank of a Bosch machine and cause the drum to jam.

Also, code F21 may appear when the voltage in the supply network drops.

Error F21 in Bosch machines without a display

Bosch washing machines without a screen indicate error F21 by flashing indicators. Here are the lights that flash depending on the car model.

• Bosch Classixx washing machines (for example, models WLF20(16)260 and WS10F260) report code F21 by flashing the second light from the bottom (the “Rinse” indicator).
• The Bosch Maxx 4 series flashes the first and third indicators from the bottom in a vertical row. These are the “Ready” and “Finish” lights.
• In the Bosch Maxx 5, 6 or 7 , the first, third and fifth spin speed indicators from the bottom light up. Depending on the model, this is 1200 or 1000 revolutions, 800 and “No spin”.

What does the error mean and why does it appear?

Error E21 most often occurs when trying to start a Bosch washing machine. The unit begins to rotate the drum only in one direction or does not rotate it at all, and then issues an alphanumeric code.

The error indicates that there is a problem with the engine electrical circuit. The following reasons can cause the E21 problem:

• control board failure;
• the voltage in the home network is too low;
• physical damage to the washing machine power cord;
• foreign objects in the drum;
• carbon brush wear;
• tachometer failure;
• short circuit in the motor windings.

Some of the listed faults can only be eliminated with the help of a service. But some problems can be easily fixed with your own hands.

On some models of Bosch washing machines, the error is displayed as code F21

Attention! Sometimes E21 appears only at the moment of switching to spin mode, and washing and rinsing proceed normally.

Decoding fault indicators

Error code E21 stands for the inability to rotate the drum. The washing machine may try to start spinning several times; if the result is negative, code F21 appears on the control panel. Failures when trying to start the reel rotation can occur for several reasons:

1. Malfunction of the Hall sensor - information about the motor speed is not transmitted to the control module and it stops the operation of the washing machine.
2. Motor failure - a faulty motor cannot rotate the drum; the module displays an error after several startup attempts. The malfunction may occur due to wear on the carbon brushes.
3. Problem with the belt driving the drum - wear, stretching, weakening, misalignment or breakage of the drive belt will cause the drum to malfunction or stop rotating.
4. A foreign object that gets into the tub during washing can jam the drum.
5. Voltage drop in the network.

To identify the cause of the malfunction, it is recommended to check all points in a certain order until the problem is detected.

Error E21 - when you can fix it yourself

The appearance of an error does not always mean that the SMA is broken. Perhaps the cause of the error is different, and you can fix the code yourself.

• The socket is acting up. Carefully inspect the outlet and plug. You may notice carbon deposits or smell something burning. In this case, you need to replace the outlet with a new one yourself or contact an electrician.
• Low voltage in the network. There is probably unstable voltage in your home. Contact your energy supply company or, if sags occur periodically, install a voltage relay.
• The control board is stuck. It needs to be rebooted. To do this, disconnect the machine from the power supply for 10-15 minutes. If there was a one-time module failure, after rebooting and resetting the error, the code will disappear.

Note! Most Bosch machines require a manual reset of the error after eliminating the cause of its occurrence. How to do this - read our article “How to reset an error in a Bosch washing machine.”

How can I prevent future breakdowns?

prevent problems that provoke error e21 :

1. 
   Before loading into the drum, the pockets of dirty clothes must be checked for the presence of foreign objects, buttons and other small accessories are checked for strength.

2. Small items of clothing, as well as underwear and socks are washed in special mesh bags.
3. Connecting the washing machine through a special voltage relay will help avoid breakdowns caused by a sudden surge in voltage in the network.

Strict adherence to all the manufacturer’s recommendations specified in the passport of the household appliance will help you operate the washing machine for as long as possible without repair.

How to fix it?

Before resetting such an error, you need to determine why it appeared. There are several variations of scenarios that can be used to fix the failure code. Typically, troubleshooting starts from basic to complex actions, one at a time. You need to act by elimination.

Important! In order to determine the malfunction, you only need a multimeter and tools for removing the mounting bolts.

Hall sensor failure

After finding out the possible reasons for the appearance of error code F21, the question arises of how to quickly detect and fix the problem without resorting to the help of a technician.

It should be noted that there is no universal way to find a breakdown.

You need to check the above reasons in a sequence convenient for you until the malfunction is identified.

First, let's figure out how to check the Hall sensor. The first difficulty you will encounter when performing this work is the inaccessibility of the tachometer and motor of the Bosch washing machine.

You can get to these elements of the washer as follows:

1. Disconnect the washing machine from the power supply,
2. Pull the equipment out into free space,
3. Remove the back wall of the Bosch machine body,
4. Remove the drive belt
5. Take photographs of the location of fasteners and wires. This is necessary so that nothing gets mixed up during assembly.
6. Remove the washing machine motor.

Before removing the engine, you must first disconnect all the wiring chips from it. Next, you need to unscrew the bolts holding the motor and press on its body. It will move forward a little. Then you need to gently pull it down.

There is a tachometer located on the motor housing. It is necessary to inspect the inner surface of the Hall sensor ring. If there are traces of grease and oxide, they should be removed. Then we check the tachometer with a multimeter. If it burns out, then replace it with a new one.

Foreign object entering the drum

If you try to turn the drum by hand with the machine turned off, a foreign object will knock or grind, interfering with the scrolling. To remove a foreign object, several steps will be required.

• First of all, you should rotate the unit so that there is unobstructed access to the MCA.
• If there is a service hatch, it will need to be opened. Otherwise, you will have to resort to dismantling the fasteners and the rear wall.
• Then you need to disconnect the wires that lead to the heating element.
• The heating element itself is also pulled out from the body part. At the same time, you can descale it.

Related article: Why water from the sink gets into the washing machine

Due to perfect manipulations, a small hole will appear through which you can pull out a foreign object. This is done using a special device or by hand.

Voltage drops

This is a dangerous phenomenon that adversely affects equipment. Voltage surges may make further use of the machine impossible. Buying a voltage stabilizer will help prevent future breakdowns. It will prevent such risks from occurring.

Tachometer failure

If the cause of a malfunction in a Bosch washing machine is a malfunction of the tachometer or Hall sensor, the following procedures will be required.

• You need to unscrew the back wall of the unit and remove the drive belt. The second action will be required to ensure that nothing interferes during the repair.
• In order not to get confused in the location of the wiring with fasteners, it is recommended to photograph them before removing them.

Important! To dismantle the engine quickly, you should initially disconnect all power from it, and then unscrew the mounting bolts.

Then you can just press on the body part and lower it. With these simple steps, removing the motor will be quick and easy.

The Hall sensor is located on the engine body. Therefore, after the engine is dismantled, all that remains is to remove the tachograph and carefully examine it. Sometimes there is oxidation or lubricant on the inside of the ring. If such a phenomenon is detected, it should be eliminated. After this, you need to use a multimeter, which will report the status of the sensor.

Important! A burnt tachograph cannot be repaired.

Motor fault

Most often, electric brushes fail. This part cannot be repaired, so you will need to buy new ones. Experts advise buying original components and replacing a pair at once. The replacement process itself is easy; an ordinary user can handle it. The main difficulty lies in the correct selection of the parts themselves.

Important! In order not to make a mistake in your choice, it is recommended to remove the old electric brushes and go to the store with them.

In this way, you can use a sample to ensure that the selected part will be suitable.

Also, on a Bosch washing machine, error F21 may appear due to a breakdown of the winding turns in the motor. Due to this, there is a leak directly onto the unit body. This type of fault can be determined by using a multimeter. In most cases, if such a malfunction is detected, it is recommended to buy a new engine, since repairing the old one will cost a large sum and is characterized by numerous difficulties.

What to pay attention to

• Frame. Dark spots and paint fading are the result of engine overheating. Occurs when the windings short-circuit. One of the reasons for motor failure and error f21.
• Shaft rotation. By turning it by hand, it is not difficult to understand whether the Bosch engine is seized or not.

Collector type

• “Weak point” – graphite brushes. They wear out during use. Extreme wear of carbon tips leads to engine failure, error f21. Remove and measure length. Less than 150 mm - replace.

Bosch washing machine brushes

Only a couple. You should take 1 contact to the store as a sample.

Brushes for commutator motors of different household appliances are different, so purchase identical ones for your washing machine: similar in size, characteristics (density and other parameters).

• Carbon deposits on the collector plates and dirt between them are the cause of error f21. During operation of the washing machine, coal dust flies off from the brushes, burning on the lamellas and getting into the grooves. Cleaning with sandpaper, rinsing with an alcohol-containing solution, and drying solves the problem with the rotation of the Bosch centrifuge.
• Winding resistance. They are checked for short circuit (R=0) or open circuit (=∞). Motors of different Bosch models differ in characteristics: 20–200 Ohms is considered normal.

Bosch washing machine winding resistance Bosch washing machine winding resistance

Direct drive (inverter) type

It is still gaining popularity, but a number of washing machine models are already equipped with such motors. It is easy to identify by the absence of a belt drive.

Direct drive (inverter) type of Bosch washing machine

The design is similar to an asynchronous motor (rotor + stator), mounted on a centrifuge. Diagnostics is difficult, but you can identify some causes of error f21 Bosch yourself.

Bosch washing machine rotor Bosch washing machine rotor

• Remove the motor cover and inspect the windings. Melted varnish, smudges, bubbles, burnt areas are signs of a short or interturn circuit. The engine is changing.
• Spin the rotor. Absence or difficulty in rotation indicates a problem with the mechanical part of the motor.

Bosch error f21 is often caused by a problem with the inverter board, which converts AC mains voltage to DC to operate the engine. It is an integral part of the motor. If the mechanics are working properly, there are no visible defects in the windings, contact service. In practice, the engine changes - faster and cheaper.

Drive belt

The belt drives the drum, transmitting engine speed. If it becomes loose or worn, transmission will be disrupted. If the belt bursts or falls off the pulley, there will be no rotation at all.

What do we have to do:

• Unplug your Bosch machine.
• Remove the back wall of the washer by unscrewing the bolts.

  

• Check the condition of the belt. Replace if necessary.
• Select the appropriate drive for your Bosch washing machine model.
• Slide the belt onto the small pulley first, then onto the large pulley, rotating it until it fits snugly.

Error F21 how to reset and fix

To fix the problem yourself, you need to follow certain steps.

1. Unplug the washing machine and wait until the water in it cools down. Then drain it.
2. Check the speed sensor. To do this, dismantle the rear wall of the unit and remove the drive belt. The tachometer is located on the motor housing. Remove it and use a multimeter to make a call. If it burns out, replace it.
3. If the engine malfunctions, first of all you should check its brushes. Quite often they wear out and then they need to be replaced. If everything is in order with the brushes, check the motor for a short circuit or broken winding turns. If this is the problem, you will have to completely change the engine.
4. If the drum jams, simply remove the foreign object from the tank that caused the breakdown. It can also jam due to a faulty bearing. If so, then change it.
5. If power loss occurs, use a voltage stabilizer.
6. When the triac fails or the reverse relay burns out, then the only way out is replacement.
7. There may also be a malfunction in the control unit. Carefully inspect the contact connections. During the washing process, the contacts may become loose and come off. In this case, just solder them.

Now let's look at how to reset error F21. Without resetting it, the unit will not work.

First switch the program to "Off". Then move the selector one position counterclockwise. Press "Start" and hold the button for a few seconds. After this, move the switch to the neutral position and wait. If it does not reset immediately, repeat the procedure several times. The error should clear.

When all of the above does not help in repairing your washing machine, call a specialist. By the way, another common error on Bosch washing machines is F16.

Repair

To understand how a tachogenerator is repaired, you need to know what it is. The tachogenerator is a metal ring to which two wires are connected. It can be used to measure engine rotation speed. The measurement information is sent to the control module.

The tachogenerator is located on the rotating shaft. However, getting to it is not so easy. First you need to disassemble the Siemens or Bosch washing machine. How to do it?

1. Turn the device towards you with the back cover.
2. Remove the cover by first unscrewing the fasteners.
3. Find the engine. The metal ring, which is located on its shaft, will be the tachogenerator.

The malfunction of this part is determined by how the Bosch or Siemens washing machine operates.

• From time to time the speed of rotation of the drum changes sharply.
• During the spinning process, the drum rotates slower than expected.
• When washing, the drum rotates much faster than it should.
• The laundry is not completely wrung out.

To make sure that error F21 in a Bosch or Siemens washing machine indicates a malfunction of the tachogenerator, you need to conduct a test:

1. First remove the engine. To do this, you need to unscrew the bolts that hold it in place and disconnect all the wires.
2. Using a special device, measure the resistance on the wires that go to the faulty part. If everything is normal, it will be approximately 60 ohms.
3. Next you need to measure the voltage on the tachogenerator itself.
4. After taking all measurements, it is recommended to check how securely the part is fastened. If the fastening is loose, problems with the operation of the entire device may occur. As a result, error F21 will appear on the display or indicators.

Replacing the broken element will help eliminate the breakdown. This is very easy to do:

1. Remove the part cover. It is usually secured with a latch.
2. Disconnect the fasteners that hold the tachogenerator.
3. Remove the faulty part and put a new one in its place.

Important Details

It is worth mentioning separately about the Bosch Maxx 5 and Bosch Maxx 7 devices. Error F21 in the Bosch Maxx 5 (Maxx 7) washing machine indicates problems with the engine. In most cases, they are caused by the brushes wearing out. The error can be eliminated by replacing the brushes. If your Bosch Maxx 5 or Bosch Maxx 7 machine still displays a fault code, it needs to be reset. Here's how to do it:

1. Close the door.
2. Set the switch to the “Off” designation.
3. Then turn it to the “Spin” program and wait until the code appears.
4. Press and hold the button that regulates the number of revolutions.
5. Turn the switch to “Drain”. Do not release the button for another 20 seconds.
6. Release the button and return the switch to its original position.
7. Repeat several times if necessary.

It is worth remembering that sometimes error F21 in Bosch Maxx 5 and Maxx 7 devices appears due to problems with the network voltage. You can eliminate it using a reset, as described above.

Error F21 in Bosch and Siemens washing machines means problems with the motor. They may be caused by malfunctions of certain parts, such as brushes or a tachogenerator. You can solve these problems yourself or by seeking help from a specialist.

Difficulties with the engine

A thorough check of the engine will be required to determine where the problem is occurring. If the malfunction occurs due to wear on the carbon brushes, it is enough to replace them. In case of other engine breakdowns, in most cases, the entire engine is replaced.

After fixing the problem, you will need to reset the error. To do this, turn the program switch to the “off” position and set the selector to “spin”. After this, wait for the code to appear on the control panel and hold down the drum speed switch button for a few seconds. Then set the switch to the “drain” position and hold down the speed switch key again. The appearance of a characteristic sound signal and the simultaneous turning on of all lights for a short period of time indicate a successful reset.

We managed to determine the cause of E21, but still need a part? Order from Samodelkin: inexpensive, fast delivery, guarantee.

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Solution: algorithm for identifying the cause and troubleshooting

Often error F21 in Bosch washing machines occurs due to loading too much laundry. If removing part of it and restarting it did not help solve the problem, you can proceed to the next verification step.

After freeing the machine from the laundry, you need to pay attention to whether the drum rotates when scrolled by hand. If it does not spin during washing, but rotates manually, the belt is checked. If the drum does not rotate manually, you should check the machine part for foreign objects. They can get into the space between the tank and the drum.

If after checking the cause was not found, not only the Bosch washing machine is checked, error E21 could be caused by a sharp drop in voltage in the electrical network.

Next, if necessary, the body parts are checked: tachometer, motor, carbon brushes.

What does an error mean: solving the problem yourself

Before troubleshooting, do the following:

1. If the wash is not completed, interrupt the program.
2. Turn off the power to the washer.
3. Drain by hand.
4. Remove the laundry and wipe the drum.

Now look at the operating instructions for your Bosch washing machine. You may have overloaded the tank with laundry, so the error cannot be cleared and the drum does not spin.

How to fix the situation: load less laundry, try running the wash again. If everything works and error F21 has been reset in the Bosch washing machine, then the problem is solved.

Motor malfunction

Models of Bosch washing machines assembled in Russia quite often experience serious problems with the motor. The simplest problem is faulty brushes.

It should be noted that brushes on commutator motors are often worn out. The technician can easily replace them. It will, of course, be more difficult for a non-professional to cope with this task. However, this work is considered quite simple and can be done independently.

The situation is much more complicated if current leaks from the motor of the Bosch device to the housing. Also, several turns of the winding may be broken in the motor. As a rule, in such cases it is necessary to completely change the engine. It will be cheaper than repairing an old motor. But first you need to check the current leakage.

To do this, you need to check the housing for leaks using a multimeter. If there is no leakage, each turn of the winding must be checked. This is necessary to detect a breakdown.

This work is quite labor-intensive and painstaking. However, after it is completed, it will be clear whether the motor has failed or not.

Hall sensor malfunction

To check the tachometer, the washing machine is disconnected from the network, after which the back panel is dismantled and the drive belt is removed.

The Hall sensor is located on the motor housing and can be removed and inspected. There may be traces of grease or oxidation on the inner surface of its ring that must be removed. Next, the sensor is checked using a multimeter. If the tachometer is faulty, it must be replaced.

Foreign object

A foreign object can damage the tank, causing water to leak and requiring costly repairs. Therefore, you need to remove it immediately:

1. Disconnect the machine from the network.
2. Pull the hatch cuff and check for objects.
3. Remove the front panel.
4. Remove the heating element.
5. If necessary, remove any remaining tissue from its tube.
6. Check the heating element hole for objects.
7. Place the Bosch machine on its side.
8. Disconnect the pipe.

Thanks to the opened hole, you can check the tank.

Control module failure

If this element malfunctions, absolutely any error may appear, not just E18. After all, it is he who is responsible for the functioning of the washing machine as a whole.

The Bosch machine control module contains many radio elements. Failure of one of them leads to a stop in the operation of washing equipment. This module is repairable. However, it is not recommended to undertake its repair yourself. It is better to entrust this work to a master. Otherwise, you may permanently break the part. And it has a fairly high cost.

Bearing failure

If the bearing is worn out, you will hear noise and hum during operation of the CM. Changing a bearing is not easy, but you can try:

1. Turn off the power to the car, turn off communications.
2. Remove the top panel.
3. Pull out the powder dispenser by pressing the lock in the middle.
4. Unscrew the screws securing the control panel and remove it.
5. Remove the bottom panel and unscrew the screws holding the front panel of the washing machine.
6. Now you need to remove the hatch cuff. To do this, remove the metal clamp using a screwdriver. Pull the cuff to access the clamp.
7. Unscrew the two bolts securing the UBL (hatch lock).
8. Bend the cuff and pull out the lock, then remove the entire panel.
9. Remove the dispenser tray and remove the counterweights.
10. Pull out the heating element and then the drain pipe.
11. Remove the motor and pressure take-off chamber.
12. Remove the tank from the springs and place it on the surface.
13. Remove the cuff from the door and turn the tank over.
14. By removing the pulley you will get to the bearing.

You can now perform the replacement.

This video will help you disassemble your Bosch washing machine and replace the bearing:

How to fix and what to do if the Bosch washing machine displays error E21

Serious engine breakdowns usually require the involvement of specialists. But in some cases, error E21 in a Bosch washing machine appears due to poor quality power supply or mechanical interference.

Unstable voltage in the electrical network

Periodic engine malfunctions can be caused by low voltage at the outlet. The problem often occurs in old apartments, where the network is not designed to handle significant loads.

You can solve the problem by calling an electrician or installing a relay. When using a Bosch washing machine, it is better not to turn on other appliances so as not to increase the load on the network.

Control module failure

If error E21 appeared in a relatively new Bosch machine, then the reason may be a random electronic failure. In this case, rebooting helps.

Necessary:

1. Turn off the washing unit using the button.
2. Remove the plug from the socket.
3. Leave the machine to stand for 15 minutes.
4. Turn the unit back on and start the wash again.

Sometimes you have to reboot your Bosch twice or three times.

Foreign object in tank

When washing, accessories, small items from pockets, or coins may fall into the washing machine tank. They prevent the drum from rotating and cause error E21.

You can remove foreign objects from the Bosch tank as follows:

1. Inspect the surface of the drum from the inside and, if possible, pull out the foreign object through the holes with tweezers.
2. If the object has fallen too deeply, dismantle the back cover, remove the heating element and look for the fallen button or coin by putting your hand into the tank.
3. Disconnect the drain pipe and try to remove the item through the opened hole.

If the object is tightly stuck, you need to remove the pulley located under the back cover of the washing machine. Then you need to move the shaft and manually rotate the drum. The item should release and fall to the bottom of the tank. After this, it remains to be removed using one of the above methods.

Warning! You can disassemble a Bosch machine only by completely disconnecting it from the network.

If there is a foreign object in the tank, attempts to start the drum are accompanied by unusual loud sounds

The power cord or plug is worn out

Error E21 in the Bosch Maxx washing machine and other models may appear due to problems with the power cord. When contacts and wires wear out, uncontrolled short circuits and openings of the electrical circuit occur from time to time.

The easiest way to fix the problem is to install a new cable. To do this you need:

1. Buy a wire with similar characteristics in the store.
2. Place the washing machine on the side next to which the powder tray is located.
3. Remove the bottom cover at the bottom of the unit.
4. Using a screwdriver, unscrew the interference filter to which the power cord is connected.
5. Disconnect the old wire and put a new one in its place.

Before dismantling the old cable, you can photograph the contact connection diagram so as not to confuse anything during the replacement process.

Call the master

In a situation where attempts to independently resolve error e21 were unsuccessful, a service center technician will help restore the functionality of the Bosch washing machine. It is enough to leave a request by phone or on the website of a specialized company (the coordinates are easy to find on the Internet). The application indicates the model of the washing machine, the year of manufacture of the device, and the essence of the problem.

A professional technician will carry out diagnostics, quickly determine the cause of error E21, and eliminate the malfunction. On average, the cost of services to eliminate the E21 error varies from 1,500 rubles. up to 5000 rub. (urgency of the order increases the amount due).

To avoid falling for scammers, before leaving a request, it’s a good idea to find reviews from those who have already used the services of the selected specialist. You cannot pay for repairs that have not yet been completed! Otherwise, there is a high risk of being left without money and without a repaired washing machine.

Reset error

For Bosch and Siemens washing machines, it is not enough to fix the problem that led to error F21. It still needs to be reset. Without this procedure, SMA SMA will not work.

Different models have their own methods. Let's consider one of them:

1. Set the program selection knob to position “0”.
2. Counterclockwise we move one division.
3. Press the “Start” button and hold it for a few seconds.
4. Return the handle to the neutral position.
5. We wait for a while.
6. The error has cleared.

It is not always possible to do it right away. Sometimes you need to repeat 5-10 times.

Important! On some models it only works when the “spin” button is pressed!

The second way to reset error F21

1. Set the program selection knob to position “0”.
2. Turn clockwise 90°. We are waiting for an error message to appear or the indicators to blink.
3. Press and do not release the spin speed selection button.
4. Then turn the program selection knob one notch clockwise.
5. Count to 20 seconds.
6. Release the spin speed selection button.
7. Return the program selection knob to the “Off” position. Strictly clockwise!

I work in the household appliance repair industry. Extensive experience in restoring washing machines and dishwashers.

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Washing machine error codes

Error codes Error description Cause of malfunction F01 Error in closing the washing machine hatch door. The hatch door is not completely closed; also check the seal for foreign objects. F02 Water does not fill into the washing machine tank. There is no water flow or low water pressure in the water supply, or there is a blockage in the inlet hose. F03 Water does not drain from the washing machine tank. An error appears on the display if the washing machine has not drained water within 10 minutes. There is a blockage in: – pipes – drain filter – drain hose The following parts have broken down: – drain pump – electronic control controller You also need to check the integrity of the connections. F04 Water has leaked into the washing machine tray. Check the tightness of the washing machine tank, pipes, and hoses for leaks. F16 The washing program does not start. Restart the washing program. A possible reason could also be an open washing machine hatch door. F17 Filling of water into the washing machine tank was not completed within the allotted time - water flow into the tank is slow. The washing program stops and the water is drained after five minutes. After draining the water, you can try to start the washing program again. There is a blockage in: – the pipes – the inlet hose, or low pressure in the water supply. F18 Water was not drained from the washing machine tank within the allotted time.

The washing program stops and an error message appears. There is a blockage in: – pipes – drain filter – drain hose The following parts have broken down: – drain pump – water level sensor F19 The water in the washing machine tank has not been heated within the allotted time. The washing program is not interrupted, the error appears after its completion. The following parts have broken down: – Heating element of the washing machine – Temperature sensor Heating element of the washing machine – Control electronic controller Or there may be a low voltage of the power supply network. F20 Spontaneous activation of the heating element during the washing program. The washing program stops and an error message appears. The following parts have broken down: – water heating sensor – heating element thermostat of the washing machine F21 Error during operation of the drive motor – the rotation speed of the drum does not correspond to the specified parameters, or there is no rotation at all. The washing program stops and an error message appears. The following parts have broken down: – tachogenerator of the electric motor – reverse relay – short circuit of the triac of the control electronic controller Check the serviceability of the connections. F22 Temperature sensor error. The washing program is not interrupted. A breakdown of the following parts has occurred: – temperature sensor. Either a short circuit of the temperature sensor or a break in its connections. F23 Water leakage into the washing machine tray - the Aquastop leakage sensor is triggered. It is necessary to check the tightness of the washing machine tank, pipes, and hoses.

It is also possible that the Aquastop leak sensor has broken down or the connections from the sensor to the electronic controller have been broken. F25 Water quality sensor error. The wash program will only run without rinsing. There is a blockage in: – pipes – drain filter – drain hose It is also possible that the water quality sensor itself has failed or the sensor sensor is dirty. F26 Analog pressure sensor error. The pressure sensor protects against voltage surges. The washing program is interrupted, the hatch door, control and display units are blocked. To reset the error, you must turn off/on the washing machine by pressing the “On/Off” button. The following parts have broken down: – the pressure sensor or its connections have been broken. F27 Pressure sensor not configured - most likely, the sensor settings have been reset. It is necessary to adjust the pressure sensor; it is also possible that the pressure sensor may break or its connections may be broken. F28 Flow sensor error. Indicates unacceptable values ​​of the flowing water volume. It is necessary to check the serviceability of the flow sensor and the integrity of its connections. F29 Flow sensor error – the sensor detects a lack of water flow. The washing program stops and the water is drained after five minutes. After draining the water, you can try to start the washing program again. There is a blockage in: – pipes – inlet hose The following parts have broken down: – pressure sensor – inlet solenoid valve Other possible reasons – low pressure in the water supply, broken pressure sensor connections.

F31 Water level error - exceeding the maximum permissible values. There is a blockage in: – pipes – drain filter – drain hose The following parts have broken down: – inlet solenoid valve – drain pump – water level sensor Also, the cause of the malfunction may be an increase in pressure in the water supply or the water pressure sensor is not configured. F34 Washing machine hatch door error - the hatch door lock is not closed. The program is interrupted, control and indication modules are blocked. The error must be reset using the “On/Off” button. The following parts have broken down: – locking lock – defective hatch cuff F36 Control error of the hatch locking device. The washing program is interrupted, control and indication modules are blocked. The error must be reset using the “On/Off” button. The following parts have broken down: – triac of the control electronic controller – relay F37 Temperature sensor error – sensor is faulty. It is necessary to check the functionality of the temperature sensor and the integrity of its connections. F38 Temperature sensor error - short circuit. The following parts have broken down: – temperature sensor F40 Synchronization error – power supply parameters do not correspond to the specified values. The power grid needs to be stabilized. F42 High speed of the drive motor, above the permissible operating values.

The washing program is interrupted, control and indication modules are blocked. The error must be reset by executing a test program. The following parts have broken down: – triac of the control electronic controller. F43 The washing machine drum does not rotate. The washing program is interrupted, control and indication modules are blocked. The error must be reset by executing a test program. The following parts have broken down: – the tachogenerator of the electric motor – the drive motor – the control electronic controller Check the serviceability of the connections. F44 The motor shaft does not rotate in the opposite direction. The washing program is interrupted, control and indication modules are blocked. The error must be reset by executing a test program. The following parts have broken down: – triac of the control electronic controller – reverse relay F59 3D sensor error – sensor measurement value is too low or too high. When this error appears, the engine speed begins to decrease. The following parts have broken down: – 3D sensor Other possible reasons are a break in its connections, a software failure. F60 Flow sensor error - value too high or low. The washing program stops and the water is drained after five minutes. After draining the water, you can try to start the washing program again. There is a blockage in: – pipes – inlet hose The following parts have broken down: – pressure sensor – inlet solenoid valve Other possible reasons – low/high pressure in the water supply, broken pressure sensor connections.

F61 Door error. The washing program is interrupted, control and indication modules are blocked. The error must be reset using the “On/Off” button. The following parts have broken down: – the lock of the hatch locking device. Other possible causes are broken connections of the hatch locking device. F63 Functional protection system error. The washing program is interrupted, control and indication modules are blocked. The error must be reset using the “On/Off” button. The control module is faulty or the software is malfunctioning. F67 Card code error. The washing program is interrupted, control and indication modules are blocked. The error must be reset using the “On/Off” button. Incorrect encoding between the control and power modules, software failure. E02 Error in the operation of the electric motor. The following parts have broken down: – the motor brushes – the drive motor – the control electronic controller Check the serviceability of the motor connections. E67 Coding error of the main control module. The following parts have broken down: – the control electronic controller. Other possible reasons are a malfunction of the software.

What does error F21 mean on Bosch washing machines and how to fix it

The situation when the washing machine stops during washing and F21 appears on the display is not so uncommon. This error code is typical for Bosh units. It means that a serious breakdown has occurred.

In machine models without an electronic monitor, such a malfunction is indicated by blinking LED indicators. For such units, a special system of flashing LED indicators has been made, which characterizes certain breakdowns.

When error F21 occurs, three indicators flash:

• rinsing;
• 800 rpm;
• 1000 rpm.

The article will discuss the search and repair of the fault indicated by error f21.

Possible faults requiring repair

If you are unable to resolve the F21 code on your own, we recommend disconnecting your Bosch from the power supply and calling a technician. He will conduct diagnostics and determine the exact cause of the error. Here is a list of the main breakdowns that cause error E 21 to come on, and the cost of fixing them.

Decoding

If the model is equipped with a display, F21 is displayed. Everything is clear here. On machines without a screen, the malfunction is indicated by blinking three spin indicators: 1000, 800 and drain.

• Tachogenerator malfunction.
• The brushes are worn out.

• The triac burned out.
• The relay that switches engine speed is damaged.

To check the first two points, you need to remove the motor. This is an important procedure that requires physical strength, as you will need to tilt the washing machine.

Let's look at the necessary step-by-step actions:

1. We disconnect from electricity and water supply, as well as sewerage.
2. Remove the top cover by unscrewing two screws. This should be done for convenience.

   

3. We dismantle the back bar.
4. Pull off the drive belt.
5. Unscrew the screws securing the engine. It is most convenient to use a ratchet wrench.
6. We turn the car over on its left side when looking at it from the front. It is important!
7. We pull out the chip and grounding.

   

8. We remove the engine.

I work in the household appliance repair industry. Extensive experience in restoring washing machines and dishwashers.

We check the tachometer generator using a tester. It should not be in a gap and produce little voltage. Please note that this failure occurs quite rarely. Bosch and Siemens motors are famous for their reliability.

Brushes are diagnosed only visually. To do this, you need to remove them from the holders, first pulling out the brass bar and removing the contacts from it.

Grinding in brushes

First of all, we check the integrity of the collector lamellas. If they start to deflate, you can sharpen them. But this is a temporary measure. Such an engine needs to be changed, or a new rotor must be found.

Be sure to remove brush dust from all accessible areas of the electric motor. We also clean it from the grooves between the collector slats.

The brushes are installed taking into account the inclination towards the rotor!

The grinding procedure is performed as follows:

1. After replacement, we install the engine in its place and fasten it. But we don't put on a belt.
2. We put on chips and grounding.
3. We start the spin program, having previously set the minimum possible speed.
4. Let's repeat it.
5. We install the drive belt.
6. We assemble the washing machine completely.
7. We don't put laundry. We choose a program lasting about an hour. We set the minimum speed. Let's launch.
8. After this, you can wash with clothes, but we load the machine halfway in the first 2-3 cycles.
9. Then we use it fully.

Module faults