First of all, if error F21 occurs, it is recommended to disconnect the Bosch washing machine from the network, since a common cause of the malfunction is related to voltage surges and further operation of the equipment can be dangerous.
There may be other problems not related to the power supply of the device, which can harm the machine during use. If there is water left in the washer, after unplugging it from the power supply, you must drain the water manually.
Reasons for the error to appear on the display
Error E21 in a Bosch washing machine may appear for the following reasons:
- A foreign object is stuck in the equipment drum.
- The power supply has dropped.
- The drive belt has slipped off the drum pulley or has broken.
- The electric motor and tachometer are faulty.
- The control module has failed.
The user can solve some problems independently. But in most situations, professional help is required.
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 in tank
When F21 appears, open the hatch and try to move the drum by hand. If it does not rotate, it may be jammed due to small debris.
You can try to remove foreign objects yourself. To do this, do the following:
- Turn off the Bosch washing machine and drain the water through the filter.
- Remove the powder dispenser, remove the control panel.
- Remove the clamp holding the hatch cuff. Thread the rubber band into the drum.
- Unscrew the fasteners and remove the front panel of the SMA.
- Disconnect the heating element wiring, move its central pin inward and, swinging, remove the heater.
- This will give you access to the bottom of the drum. Remove items that are causing it to jam.
After this, you need to assemble the washer in reverse order. If you doubt your own abilities and know that you cannot perform the above steps on your own, contact 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.
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Power surges
It happens that the drum does not rotate due to insufficient voltage in the network. Checking the voltage level is not difficult.
Disconnect the equipment from the power supply and unplug the vetch from the outlet. Then, using a multimeter, check the voltage in the outlet and compare it with the parameters specified in the technical data sheet for the equipment. If the voltage does not meet the required one, you need to contact a professional, because... Electrical problems should be resolved by suitably qualified professionals.
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:
- Disconnect the washing machine from the power supply,
- Pull the equipment out into free space,
- Remove the back wall of the Bosch machine body,
- Remove the drive belt
- Take photographs of the location of fasteners and wires. This is necessary so that nothing gets mixed up during assembly.
- 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.
Tachometer and engine
The tachometer transmits signals about the speed of rotation of the motor. If it is broken, the module will not receive the appropriate commands, and the drum will, as a result, stop rotating. It is necessary to measure the resistance of the tachogenerator contacts and, if the readings are less than or more than 60 Ohms, the part should be replaced.
If the motor is broken, the drum will be turned manually. The motor is also diagnosed and, if necessary, replaced.
To replace the tachometer or motor, you need to disassemble the body of the Bosch washing machine. In addition, the components must be carefully disconnected from wires and other parts. In this case, high-quality repairs can only be performed by professionals, so if there are any malfunctions in the operation of the AMS, immediately contact the service center.
Interpretation of error F21, E21 and causes
If the model is equipped with a display, F21 (E21) is displayed. Everything is clear here. On machines without a screen, the malfunction is indicated by blinking three spin indicators: 1000, 800 and drain.
Causes:
- Tachogenerator malfunction.
- The brushes are worn out.
- The triac on the control module burned out.
- The relay that switches engine speed is damaged.
Control module
The controller fails due to power surges or moisture. This is the “brain” of the equipment, so if it is faulty, any malfunction may occur in the operation of the Bosch washing machine, incl. and no drum rotation. The module is located behind the control panel. First of all, it is diagnosed. If the controller has scorch marks, swollen capacitors, or burnt out tracks, it can be repaired. In case of more serious damage, the board assembly is replaced. Of course, a master should deal with electronics.
It is important to call a service center specialist if there are any signs of malfunction of the washing machine. Unskilled intervention can damage the equipment forever. Therefore, it is better not to take risks, but to contact the service center immediately when error E21 appears on the unit display.
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.
Motor brushes - from 1400 rubles.
The graphite brushes in the motor are responsible for transmitting voltage from the stator to the rotor. As their length decreases, the motor power decreases. With a non-critical reduction in brushes, Bosch can spin the drum during the wash, but does not gain speed during the spin cycle. When the length of the brushes becomes less than 1 cm, there is no rotation at all.
Brush abrasion is the most common cause of error F21 in Bosch.
Signs
Bosch does not spin the drum at all or cannot spin. Perhaps the SMA is sparking. On the screen there is code E21.
How to fix
The brushes must be replaced with new ones.
Control unit firmware failure - from RUB 2,000.
All work programs are stored in it. Most often, this problem occurs after power surges.
Signs
Code 21 appears immediately when turned on, but the drum does not rotate.
How to fix
The technician removes the memory chip from the control unit, reprograms it and solders it in place.
Control unit - from 2000 rub.
The radio elements in the motor circuit fail or the tracks on the board burn out. The motor control triac or reverse relay is often faulty.
Signs
A Bosch washing machine may not spin the drum at all or only rotate in one direction. The error first appears after filling with water. But in some cases it can occur at any stage of the program: in this case, the cycle breaks down.
How to fix
The technician diagnoses the control unit and:
- replaces failed elements (triac, relay and others);
- solders burnt tracks;
- if the board is extensively damaged, replace it with a new one.
Tach sensor - from 2000 rubles.
It determines the rotation speed of the motor and is located on the rotor. Often the tachometer coil burns out or the magnet becomes unscrewed.
Signs
The Bosch machine does not rotate the drum and shows an error.
How to fix
The technician “rings” the tachometer and, if it is burned out, replaces it with a new one. If a magnet comes loose, the technician screws it back on.
Motor - from 2000 rubles.
There is probably a break or short circuit in the rotor or stator windings. Sometimes the reason is a breakdown in the body.
Signs
The washing machine takes in water, after which it writes error E21 or F 21. The drum does not rotate. Sometimes the SMA can knock out an RCD or machine gun.
How to fix
The technician inspects the motor and, based on the type of failure, repairs it or replaces it with a new one.
Foreign object in the tank - from 1300 rubles.
Clothing accessories (a bra wire, a zipper catch, etc.) or things from pockets (coins, a toothpick, etc.) got there. They prevent the drum from rotating and cause an error.
Signs
The Bosch washing machine makes loud noises: it knocks, rattles and the drum does not rotate well. The error can occur both during washing and during rinsing or spinning.
How to fix
The foreign object must be removed from the tank. You can do it yourself or order it.
Bearing wear - from RUB 3,300.
During long-term operation of the SMA, due to vibrations, the tightness of the seal is broken. Moisture gets into it, which leads to bearing corrosion and destruction. If the process has just begun, Bosch rattles only during the spin cycle. When the bearings are destroyed, they completely block the rotation of the drum.
Signs
The machine makes a lot of noise during the spin cycle and does not spin. It is possible that the drum does not rotate at all.
How to fix
It is necessary to replace the bearings and oil seal with new ones.
Plug and/or power cord - from RUB 1,400.
Due to wear of the plug and/or cord, the phenomenon of “contact bounce” occurs when, when the circuit is closed, uncontrolled closing and opening of contacts (electrical breakdowns) occurs.
Signs
Error F21 occurs periodically. Sometimes the machine goes through the entire cycle normally, other times an emergency code is displayed.
How to fix
The technician “rings” the Bosch CMA plug and cord and, based on the diagnostic results, replaces it/them with a new one/s.
Broken wiring or contacts in the motor circuit - from 1,500 rubles.
Probably, due to vibrations, the contacts became loose/burnt out or the wiring was damaged. In the private sector, wires can be chewed by mice and rats.
Signs
Bosch starts the wash, draws water, but the drum does not spin, and the machine displays code E 21 or F 21 on the display.
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.
Adviсe
Often code e21 is a signal that the washing machine drum is overloaded . To understand whether this is true, you need to unplug the power cord from the outlet, manually drain the water, reload the drum, and start a new wash cycle.
After the cause of error e21 has been eliminated, additional steps must be taken to reset the error. How to reset the code? To do this, set the selector switch to the “Off” position, then “Spin”, hold down the drum speed switch button for a few seconds, set the selector knob to the “Drain” mode, and press the speed switch button again for a couple of seconds.
What does an error mean: solving the problem yourself
Before troubleshooting, do the following:
- If the wash is not completed, interrupt the program.
- Turn off the power to the washer.
- Drain by hand.
- 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.
