53640/33640 - 53644/33644

DIAGNOSTIC TROUBLE CODE 53640/33640, 53641/33641, 53642/33642, 53643/33643, 53644/33644

Motor Fault





Diagnostic Trouble Codes

xx640 Current consumption of a motor. > 50a

xx641 Seat front edge motor current consumption. >50a

xx642 Legroom adjustment motor current consumption. > 50a

xx643 Seat rear edge motor current consumption. >50a

xx646 Backrest motor current consumption >50a

Fault Symptom

The motor does not operate, neither manually or at memory setting.

Feasible fault causes

- The motor is faulty.

- Short circuit between the motor connections.

Diagnostic Procedures





1 Check the voltage supply to the motor.

- Unfasten the motor sensor connector.

- Measure the voltage at pin 1 and pin 2 of the sensor connector.

- Run the motor in both directions with the manual controls.

The voltage between pin 1 and pin 2 should alternate between +12v and -12v (battery voltage) depending. On which direction is chosen.

Are both voltage readings correct?

YES Change the motor.

NO Inspect and possibly rectify the wiring between the motor and the electronic control module. If the wiring is free from fault, continue with point 2.

Important: The backrest motor must not be test run with any other voltage supply than the electronic control module. Using another voltage source can cause the seat to travel past the potentiometer end positions. The potentiometers then slide on the motor shaft and their calibration is destroyed (the backrest has faulty end positions).

2 Final inspection

- Perform Complete Operation Check. Component Tests and General Diagnostics