Error F43 on Bosch machines - causes and solutions

If a Bosch washing machine displays error F 43, first of all you need to figure out what the code means, how to clear the error and restore the machine’s functionality on your own.

In this article we will look at the main signs and causes of the error. We will also tell you what to do if code F43 lights up on the display of your SMA.

How to fix a mistake: do-it-yourself repair

The error requires immediate repair, as it may be associated with a breakdown of important components of the Bosch washing machine.

Having detected fault codes, service center technicians carry out diagnostics and the corresponding set of actions. Based on their experience, we can conclude that the solution to the problem is as follows:

You need to check the drum with your own hands to see if it rotates freely.
Replace bearings.
Repair (reprogram) or replace the control unit (electronic controller).
Replace the tachogenerator.
Repair the engine.

Important! It is worth understanding that the error is critical: the motor may have overheated, and it urgently needs to be repaired or replaced. Do not use the washing machine with error F43 - this may result in a short circuit and possible fire.

Independent actions

It's worth starting small - something that can be done without special tools and experience: check the drum for overload or find an object blocking the rotation of the drum, if this is the reason.

To check if the machine is overloaded, stop the wash, remove some of the laundry and restart the program. If the code disappears, then the error reset was successful.

Foreign object removal

Any small or not very small object can block the drum. Masters, sharing their experience, say that in their practice, the drum in Bosch brand washing machines was blocked due to debris, small coins, buttons, cufflinks, and even socks and tights.

To confirm that a foreign object is preventing the drum from working, you will hear a characteristic knocking or noise. Bosch washing machine fault codes accompanying this failure do not always appear.

Typically, the item is located:

At the bottom of a tank or drum.
Between the drum and the walls of the tank.
Wrapped around the drum.

To find out where the interference is, unplug the machine and turn the drum by hand. By knocking you will almost immediately find out where the object is. If you can’t find it right away, arm yourself with a flashlight to carefully inspect the space behind the wall of the tank.

WHAT YOU NEED TO CHECK FIRST

Before disassembling the machine to check the internal components, you need to check whether the tub is blocked by a foreign object that got stuck during the wash. To do this, you must manually rotate this part of the washing unit. If the tank rotates freely, this is not the reason.

The machine may be overloaded with laundry, and the motor is unable to wash or spin. It is necessary to lay out excess laundry, and in the future do not exceed the load norm.

The tank may not rotate due to a bearing that has completely failed and cannot cope with its functions.

✅ Call our master to your home for FREE: +7-982-231-69-66 .

ROOT CAUSES

If nothing prevents the free rotation of the drum, you need to disconnect the machine from the network, from the water supply and begin diagnosing other possible causes of the breakdown. To do this, you will need tools such as screwdrivers and a multimeter.

Washing machine motor diagram

Remove the back panel by unscrewing a few screws. After this, the engine of the unit will appear to your attention. It's at the very bottom.
Check to see if the belt has come off the pulley or motor shaft.
If the problem is not in the belt, you need to remove it, unscrew the motor mounting screws, and disconnect the connectors.
Check the brushes. It is the wear of these components that often leads to problems. Each brush must be more than 1 cm. Faulty brushes can be replaced.
Check the connectors.
Check the wires.
Check the condition of the winding.

If everything is fine with the “heart” of the washing machine, the problem may be in a small device called a tachometer. This component is installed directly on the motor and records the number of revolutions. The readings are transmitted to the electronic module. If its operation is disrupted, the drum rotates too often or does not rotate at all, which can cause error F43 to appear on the display. The faulty tachometer must be replaced with a new part.

Sometimes, after repairing a failed part of the mechanism, the error code still continues to appear. A service test will help you reset it. To carry it out, closing the hatch door, you need to press a certain sequence of keys using the rotation handle. Each model of Bosch washing machine has its own.

REPAIR IN THE WORKSHOP

As you can see, eliminating error F43 is not always an easy task. It is easier for an experienced technician to find the cause, especially if it is related to the engine or tachometer. Then you won’t have to spend time on your own, look for the right spare part, or dismantle elements. In addition, the technician knows all the nuances of conducting a service test, which is not intended for ordinary users.

Contact our service center, and error F43 of the Bosch washing machine, no matter what caused it, will be eliminated as soon as possible!

✅ Call our master to your home for FREE: +7-982-231-69-66 .

Decoding Bosch errors

E01

There is no signal to block the hatch. Bosch electronics evaluates the situation as the machine is not ready for operation and the wash cycle does not start. The lock indicator light flashes or lights up.

Causes

Loose door hinges. Tightening the screws clears the Bosch error.
Deformation, change in position of the seal. The cuff prevents the loading hatch from closing tightly, and the automatic system displays error F01 of the washing machine. Inspect, correct. If the rubber product is damaged, install a new product.
Handle malfunction. Replacement - there is no other solution.
Breakage of the guide pin, displacement of the clamp. If there is no mechanical damage, it is enough to put the bushing and tongue in place.
The washing machine error is related to the UBL problem . The hatch lock differs in design and layout depending on the Bosch model and year of manufacture. A problem with the mechanical part of the UBL is indicated by the locking of the door after the end of the wash - the hatch does not open. To test the circuit, the device must be removed. The resistance between the neutral contact and the phase contact is checked. The multimeter does not show the R value as a three-digit number, the cause of the Bosch error has been found (thermal element). The measurement is also carried out between the neutral and common contacts of the lock: R=0 or ∞ – a sign of a malfunction of the UBL.

Testing the hatch locking device

E02

Problem filling the washing machine tank. The Bosch program provides for the supply of a certain amount of liquid (depending on the mode) during the estimated time. Failure to meet this condition triggers error E02.

Causes

The pressure in the water supply has decreased.
The water supply valve is closed.
The hose between the pipe and the washing machine is clogged or pinched.
The Bosch error is caused by a malfunction of the intake valve, the inlet filter. Mesh contamination is a common cause of code 02. Rinse and the Bosch error will disappear.
Pressostat failure. The level sensor does not send information to the electronic board about water entering the tank. Check the contacts of suitable signal lines and the condition of the capillary. The Bosch error is caused by damage to the plastic of the tube, a bend, or “garbage” in the cavity. The device is installed under the top panel of the washing machine, attached to the side (left) wall.

E03 (E18)

There is no (or slow) drainage of dirty water from the Bosch tank. Similar to error 02 - the condition of the washing machine program is not met.

Causes

Sewer blockage. It’s easy to check - open the mixer valve, make sure that the water from the sink (bathtub) goes into the drainage system.
Hose for draining water into the sewer. Kinking of the sleeve is a common cause of error 03. Rubber rubber requires periodic cleaning - over time, dirt accumulates on its inner walls, the fluid flow channel narrows, the speed drops, which causes the appearance of the 3rd code.
Filter. Serves to protect the pump from debris (fibers, buttons, rivets, coins) from the washing machine tank. Remove, perform mechanical cleaning, rinse, the Bosch error will be removed.
Transition elbow. Connects the outlet pipe of the pump to the drain hole of the washing machine. Clogged with dirt - error 03 appears.
Drive unit. Loosening, breaking of the belt. Correct, replace, and the problem will disappear.
Pump. A drain error is caused by broken contacts or a malfunction of the device.
Incorrect operation or breakdown of the Bosch pressure switch.

E04

The error informs about a leak from the machine. Sometimes, after finishing the washing process, Bosch does not drain the water.

Causes

After maintenance, the drain filter is not installed tightly.
Unreliable dispenser connection.
Leak in the water supply hose at the connection to the washing machine.
Deformation or damage to the door seal.
Defect in the adapter pipe (pump outlet).
Bosch tank leaking.
Pump malfunction (wear of seals, cracked housing).

E16

The error appears if the Bosch hatch is not completely closed. UBL “does not see” the tight fit of the door, the automation blocks the operation of the washing machine. The reasons are indicated in the description of code E01.

E17

The error appears at different stages of operation of the washing machine:

rinsing: no water flow into the Bosch tank;
wash: slow set;
Starting the washing machine: the tank does not fill with water.

The error indicates that the time allotted by the program for collecting liquid into the washing machine tank has been exceeded. The troubleshooting method is described for code 02.

If it is written E17, but there is a systematic intake/draining of water from Bosch, the reason is illiterate connection to engineering systems, non-compliance with the manufacturer’s recommendations. The drain hose in one of the areas should be located above the washing machine tank.

Left-side connection of the drain hose of a Bosch washing machine

E19

The error is interpreted as a heating problem. The time allotted for raising the temperature of the liquid in the Bosch tank to the desired value does not correspond to the program.

Causes

Mains voltage: low Uc value. It is easy to check by turning on another electronically controlled household appliance. Malfunctions are observed - the cause of the washing machine error has been found.

The stabilizer eliminates the risks of the influence of the electrical network on the functioning of Bosch.
Expert opinion

There is a problem with the heating element power circuit . Wire short circuits, increased leakage current due to worn out braiding.
Lime deposits on the surface of the heating element. A common cause of washing machine errors is if “hard” water is used. Mechanical cleaning is ineffective - the heater is changed.
Incorrect operation of the temperature sensor.

Bosch washing machine temperature sensor

Bosch washing machine heating element

Installation location of the temperature sensor of the Bosch washing machine

To check its functionality, the temperature sensor is removed from its installation site (panel with heating element). Access - after dismantling the rear wall. Testing is carried out with a household multimeter. The resistance of the device is measured at different temperatures. The sensor has an inverse relationship between R and t0 (negative coefficient). Most Bosch SMAs have a thermistor with a resistance of 6±0.5 kOhm at t0 = 20 0C.

Remove, let cool, measure at room temperature. Immerse in heated water, wait 10 minutes (response time), re-determine R of the device - the value should decrease (at 50 0C about 1.3). The readings do not change - the reason for the washing machine error, install a working sensor.

E20

The error appears when the water in the Bosch tank spontaneously heats up.

Causes

Temperature sensor failure.
The heating element relay is faulty (on the control board).

E21 (43)

Explanation: The drum does not rotate.

Causes

It jumped off the pulley, broke, and the drive belt became loose.
A foreign object (button, coin) blocking the free movement of the Bosch drum.
Faulty speed sensor, break, short circuit of signal lines.
Problem with the washing machine motor. For commutator-type motors, a common cause of error is extreme wear of the brushes. It is necessary to monitor the condition and regularly install new products.

A pair must be replaced, even if one contact is usable.
Expert opinion

Bearing failure.
Carbon deposits on the engine manifold, dirt between the lamellas. The error can be cleared by cleaning.
Centrifuge overload. If the weight of the laundry exceeds the norm, the engine power is not enough to spin the drum. Removing some things solves the problem of error 21 (43).

E22

No heating. The appearance of such an error is often associated with a malfunction of the temperature sensor or defects in the loop (lack of contact, break, short circuit). Check the filling level of the tank - if there is a lack of water, the electronics does not give permission to turn on the heating element.

E23

Error informing about a leak, the Bosch Aqua-Stop function is activated. In a number of washing machine models, the bottom is covered with a tray. It has a sensor that reacts to the appearance of water.

Causes

Depressurization of the tank, connections in the hydraulics of the washing machine.
Malfunction of the leakage sensor or cables suitable for the sensor.

E25

Triggering of the aqua sensor. This washing machine sensor monitors the purity of the water, determines the need for additional rinsing, and replenishing the volume of liquid in the tank. Its failure is the cause of the Bosch error.

Aquasensor for Bosch washing machine

Causes

Malfunction of the sensor is caused by contamination of the sensitive element (detergent residue, scale) or a malfunction in the electrical circuits.
The tap water is not clean enough.
“Garbage” in the drain and fill path of the washing machine.

E26 (27, 60)

The volume of water in the tank is not determined. The automation evaluates this as a lack of fluid collection/draining. This error is often associated with a problem with the pressure switch. Incorrect operation of the level sensor, unreliable contacts, clogged capillary tube.

E28 (29)

Washing machines have a sensor that measures the flow rate of the water being poured. Unlike a pressure switch, it controls not the level, but the pressure. Different Bosch models have a separate device or built into the inlet valve. Its breakdown or incorrect operation is the cause of the error.

Sensor measuring the flow rate of a Bosch washing machine

What to do

Check the pressure in the cold water pipe.
Eliminate kinks in the hose, blockages in the supply hose and filter.
Assess the condition of the sensor and cables, clean the device pipes.

E31

The error appears when the washing machine tank is overfilled.

Causes

The level sensor does not work.
The drain path is blocked.
Pump failure.
Blockage in the sewer.
Violation of the instructions for connecting Bosch to engineering systems. Check the position of the connecting sleeves and eliminate any deficiencies.

Bosch washing machine hose and cable length

E34

The hatch is not blocked. Recommendations are described in error 16. With code 34, the mechanics of the door lock or hinge are often at fault.

E37 (38)

The error indicates the temperature sensor of the washing machine. Code 37 – sensor failure, 38 – short circuit in thermal resistance or wiring.

E40

The manufacturer Bosch guarantees trouble-free operation of the washing machine with network parameters of 220–240V/50Hz. The error is caused by a mismatch in the supply voltage values or a shutdown (triggering of an AV, RCD on the line).

E42

The engine speed exceeds the permissible value - the meaning of the Bosch error.

Causes

No signal from the tachometer.
Engine malfunction.
Control board failure.

E44

The error occurs due to the lack of reverse rotation of the centrifuge.

Causes

Reverse relay malfunction.
Centrifuge overload.
Bosch control board failure.

E59

Invalid data from 3D sensor. The wash cycle does not complete.

Causes

Problem with sensor lines.
Damage to the device cable - Bosch electronic board.
There is a malfunction in the “brain” of the washing machine. In some cases, a “reflash” is required to remove the error.

E61

If this error occurs, the door does not lock and the washing cycle does not start. The problem is related to an incorrect signal about the position of the hatch.

Causes

Faulty UBL or loop.
Failure in the Bosch electronic board.

On a note

The “brain” of the washing machine also generates other errors, descriptions of which are not found in the Bosch documentation or complete information is not given: E5–15, 24, 30, 32, 33, 35, 36, 39, 41, 45–56, 58, 62 –67. These codes indicate a problem with the control module. Self-repair, based on the advice of friends, from the Internet is not recommended.

Diagnostics cannot be performed without a special stand that simulates the operation of a washing machine, diagrams, practical experience, and the necessary tools.
Bosch control boards are different: depending on the year of manufacture of the CMA and the model. If someone managed to find a faulty radio component on the control panel, it is not a fact that it will help other users to remove the error.

85% of units that cannot be restored are the result of unprofessional intervention in the design of the washing machine, or attempts to reinstall the software. If you cannot cope with the error, contact an authorized service center.

But first, try to identify the cause of the Bosch problem by inspecting the board . Both sides of the panel are subjected to visual inspection, so the block is removed.

How to proceed

Check the cables, reliability of contacts, condition of connectors.
Remove white stains, dust, traces of thermal effects, and condensation from the surface. Solvents are not used for cleaning: soft swab and aviation gasoline or alcohol-containing liquids. After drying the board, check the washing machine for operation - this technique eliminates a number of errors.
Inspect the paths carefully. Fault codes are a consequence of unreliable contacts at solder points, cracks, peeling, and short circuits. Defects are eliminated by soft soldering or bypassing the problem area: a parallel circuit is created with a piece of mounting wire.
Pay attention to the housings of electrolytic capacitors. In an unusable container, the “barrel” cylinder is deformed (inflated). Replacement removes errors.

If you have experience in correcting on Bosch washing machines , write in the comments to this article, we will try to consider your option and analyze it in detail in this or one of the following articles . Send photos and videos with comments and descriptions.

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Similar errors and malfunctions

Where did the code come from?

As a rule, this error is displayed if the machine has difficulty rotating the drum or operating the motor. By the way, the presence of this kind of problem is not necessarily accompanied by a code; sometimes the behavior of the unit reveals problems - the machine literally rotates the drum through force, while literally bouncing in place. In turn, there may be several reasons for this.

Failure or malfunction of the tachometer. The function of this element is to notify the electronic module about the operating characteristics of the engine. When something is wrong, the car's brain simply does not understand what is happening to the engine. The solution is to replace the tachogenerator.
Damage to the control unit. It is difficult to do anything with your own hands; only a qualified specialist can diagnose and repair the breakdown. Perhaps everything is fine with the motor and drum, the machine just doesn’t understand it.
Bearings are worn out. Bearings are metal rings that act as a connecting link between the cross and the drum. During active use, they are the first to fail. If you start the problem, the next thing in line will be the cross, and then not far from the drum. The part can be safely replaced to prevent problems in the future.
A foreign object has blocked the drum. Even if you take out change from your pockets, fasten the locks, etc., this is not a guarantee that the drum is not in danger. There are known cases when a bra wire blocked the operation of the SM, and then completely pierced the tank. No one is immune from such a problem, so it only needs to be solved promptly, then, perhaps, expensive long-term repairs will not be required.

Important! Do not forget that overloading the drum can also cause error F43. Nothing will happen just once, but if you do it regularly, then defects will inevitably appear.