Electrolux T5675 Service Manual page 143

21:3 NO INTERLOCK
This error code is generated by the MCU for drum motor.
The MCU must be powered with 230V / 50 or 60 Hz on the interlock input in order to drive the motor.
This signal is a confirmation that the door is closed and locked.
MCU receives its commands to rotate the drum from the CPU via a serial communication link
between the MCU and CPU. Since the CPU also has access to the interlock signal, the CPU must
never send a run command to the MCU if the interlock signal is missing. If this does happen,
this error code will be shown.
Possible causes:
The cause of this error code being activated can be e.g. a break in the cable leading the interlock
signal to the MCU. There may also be an error in the connector in the door lock, which connects
230V / 50Hz to the interlock signal. An error in the interlock circuits of the MCU can also set this
error code.
Recommended actions:
1. Use a multimeter to check that the interlock signal is present on X302:1-2 when the door lock is
activated. Read also bit 1 in the second byte under MCU STATUS in the service program (the
bits are numbered from 0 to 7 where bit 0 is on the far right). If bit 1 in the second byte is 1 then
the lock is open, while a 0 indicates that the lock is closed.
2. Replace the defective part.
21:4 NO COMMUNICATION
This error code is generated by the MCU for drum motor.
MCU detects there is there is a problem in communication with CPU.
Possible causes:
Bad contact in harness or connectors between CPU and MCU.
Recommended actions:
1. Check wiring, connections between CPU and MCU.
Troubleshooting
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