What Does Error Code E45 Mean on a Siemens Washing Machine?
Reset the machine by switching it off at the wall socket, waiting 5 minutes, then switching it back on and restarting your programme — this clears temporary communication errors in the control module (takes about 5 minutes).
Fault description
Error code E45 points to a breakdown in communication between the main control board (PCB) and one or more of the electronic components it needs to talk to — such as the motor control unit, door lock module, or display board. When this communication link fails or sends garbled signals, the machine cannot safely continue a wash cycle and stops to protect itself.
When E45 appears, the washing machine will typically pause mid-cycle or refuse to start at all. The drum may stop spinning, and the programme indicator lights may flash or behave erratically. In some cases the door will remain locked until the fault is cleared.
The good news is that E45 is sometimes caused by a temporary electronic glitch rather than a failed component, so a straightforward reset is always worth trying first before investigating further.
Causes
- Temporary electronic glitch in the control module — A brief power fluctuation or voltage spike can cause the control board to lose its communication state. This is the most common trigger and is often resolved by a full power reset.
- Loose or corroded wiring harness connector — The ribbon cables and plug connectors linking the main PCB to sub-components can work loose over time due to vibration. Corrosion on connector pins can also interrupt the data signal.
- Faulty main control board (PCB) — If the control board itself has developed a fault — due to age, moisture ingress, or a component failure on the board — it may be unable to maintain reliable communication. This typically requires board replacement.
- Faulty motor control module — Some Siemens models use a separate inverter or motor control unit that communicates with the main PCB. If this secondary module fails or develops an internal fault, E45 can be triggered.
- Defective door lock assembly — The door interlock sends status signals back to the control board. A failing door lock can send incorrect or no signals, which the PCB may interpret as a communication error.
- Damaged wiring between components — Physical damage to the wiring loom — caused by wear, pinching during installation, or rodent damage — can break the communication circuit entirely. This is less common but worth checking if connectors appear intact.
Step-by-Step Fix
- 1
Perform a full power reset
Turn the programme dial to the off position, then switch the machine off at the wall socket. Leave it unplugged for at least 5 minutes to allow the control board to fully discharge. Plug it back in, select a short programme, and press start to see if the error has cleared.
- 2
Check the door is fully closed and latching correctly
Open and firmly close the door, making sure you hear a clear click from the latch. A door that is not fully engaged can prevent the lock from sending its confirmation signal to the PCB. Try starting the machine again after re-closing the door.
- 3
Inspect the door lock assembly for visible damage
With the machine unplugged, examine the door lock mechanism through the door aperture. Look for cracked plastic, a stuck or broken latch hook, or scorch marks around the lock body. A visibly damaged door lock will need to be replaced.
- 4
Check the wiring harness connectors at the control board
Remove the top panel of the machine (usually secured by two screws at the rear) to access the main PCB. With the machine unplugged, gently press each connector firmly into its socket on the board to ensure a secure connection. Look for any pins that appear bent, corroded, or discoloured.
- 5
Inspect the wiring loom for visible damage
Trace the main wiring harness from the control board toward the motor and door lock. Look for any sections where the outer insulation is worn, pinched, or melted. Damaged wiring sections will need to be repaired or the loom replaced — do not attempt to run the machine with exposed wiring.
- 6
Test with a different programme
If the machine powers on without immediately showing E45, try a different wash programme such as a quick 30-minute cycle. Some programme-specific faults can mimic a general communication error. If E45 only appears on certain programmes, note this when speaking to a service technician as it helps narrow down the faulty component.
- 7
Consider replacing the main control board or motor module
If all connections are secure and the error persists, the fault is most likely within the main PCB or the motor control module itself. These are internal electronic components and their replacement is best carried out by a service technician, though the parts can be sourced independently if you are confident working with appliance electronics.
Affected models
Select your model to see its full troubleshooting page.
When to call a service technician
If the error code returns immediately after a power reset, or if you have checked all connectors and found no obvious wiring damage, the fault is likely inside the control board or motor module — components that require specialist diagnostic tools to test accurately. Attempting to replace a PCB without confirming it is the faulty part can be an expensive mistake.
You should also call a service technician if you notice any burning smell, scorch marks on the PCB or wiring, or if the machine trips your household circuit breaker when switched on. These are signs of an electrical fault that must not be ignored.
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Frequently Asked Questions
Can I still use my Siemens washing machine with error code E45 showing?
It is not advisable to continue using the machine while E45 is active. The error means the control system cannot communicate reliably, so the machine may behave unpredictably — for example, failing to stop filling with water or not spinning correctly. Resolve the fault before running further cycles.
Will a factory reset clear the E45 error on a Siemens washing machine?
A power reset (unplugging for 5 minutes) is the equivalent of a soft reset and is the recommended first step. Siemens washing machines do not have a user-accessible factory reset function in the way that smart devices do. If the error returns after a power reset, the underlying hardware fault needs to be addressed.
How much does it cost to replace a Siemens washing machine control board?
A replacement main PCB for a Siemens washing machine typically costs between £80 and £180 for the part alone, depending on the model. If you are paying a service technician to fit it, labour charges will add to this. It is worth getting a diagnostic visit first to confirm the board is actually the faulty component before purchasing.
Is error code E45 the same as a door lock fault?
Not exactly — E45 is a communication error, but a failing door lock can be one of the causes. If the door lock is not sending its signal correctly, the PCB logs it as a communication breakdown. If your machine also shows signs of a door that will not lock or unlock, the door lock assembly is a strong suspect.
How do I find the model number on my Siemens washing machine?
The model number (E-Nr) is printed on a label inside the door aperture — open the door and look around the inner rim of the drum opening. You will need this number when ordering spare parts or booking a service visit to ensure the correct components are supplied for your specific machine.