Electrolux T5675 Service Manual page 144

144
21:5 MOTOR SHORT CIRCIUT
This error code is generated by the MCU for drum motor.
The MCU reads the power consumption of the motor continuously. If the current for some reason
exceeds a predetermined limit, the MCU will cut the current to the motor. After the motor has
stopped (= tachometer indicates stationary motor), the MCU will attempt to restart it. If the MCU
then detects high motor current again, this error code will be activated. If on restarting after a first
short circuit, the MCU rotates normally, the error code will not be shown.
Possible causes:
This error code can be activated for a number of reasons:
• Short circuit in motor. Measure motor windings with a Motor Tester.
• Short circuit internally in motor winding (impaired efficiency, higher current consumption).
• Short circuit in motor cables.
• Short circuit in connectors.
• Drops of water causing short circuits in the motor connector.
• Short circuit in the MCU output transistors.
• Bad contact in tacho signal.
• Bad contact in interlock signal.
Recommended actions:
1. If the error is a stable one, it is generally not difficult to locate the defective unit through resistance
measurement and testing with the service program. Measure motor windings with a Motor Tester.
2. Further information can be obtained by studying the contents of MCU ERROR LOG 1 and MCU
ERROR LOG 2. Review following:
SHORT CIRCUIT 2 (specifies how many times the error code has been active).
SHORT CIRCUIT 1 (specifies how many times the current limit has been exceeded. The
difference between short circuit 1 and short circuit 2 indicates how many times there has been a
short circuit 1 that has not been confirmed when restarting the motor).
LAST FAULT CODE N/8 (shows the 8 latest error codes).
TACHO ERROR LOW SPEED (can give a clue in case of intermittent errors).
TACHO ERROR HIGH SPEED (can give a clue in case of intermittent errors).
21:6 INTERLOCK HARDWARE
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.
The interlock circuits in the MCU have been split into two channels so that a component error in
MCU cannot give a false confirmation that the door is locked. These two channels are checked
against each other. If this check gives an incorrect result this error code will be shown.
Possible cause:
The reason for this error code being activated can be attributed to an error in the interlock circuits
in motor control.
Recommended actions:
1. Replace MCU.
Troubleshooting