Fault code 0325: Diagnosis/troubleshooting

NOTE: Visual inspection: In the next troubleshooting section, please check first that the affected pins on the rear convenience system control unit plug connection are neither damaged nor corroded. The wiring and plugs of the affected components must also be checked for external damage and correct contacts. Repair damaged or corroded pins if possible, otherwise replace affected pins. Repair or replace damaged wires.

NOTE: Sporadic faults: In the event of faults that occur sporadically, the wiring positions that are linked to moving parts on and in the vehicle must be checked for each system. Various statuses that can cause faults must be simulated with the help of the wiring diagram.

NOTE: Battery voltage: A battery voltage of between 11.4 and 14.5 V is required for the following troubleshooting procedure. This must be checked and provided, if necessary. On the vehicle electrical system, the voltage to the fuse (input side) must be guaranteed.

NOTE: This fault is detected if there is ground potential for more than five minutes on plug A, pin 3.

NOTE: In the rear window area (right) of the wiring harness there is a 6-pin plug connector and in the rear window area (center right) a further 2-pin plug connector that must be included in the checks.

WORK INSTRUCTION CHART

Work instruction			Display OK	If not OK
1	Check rear window switch	Use the 9588 System Tester II to switch to the menu "Input signals/Rear window switch (outer button)". Pull plug off rear window switch.	Status of momentary-switch handle of rear lid changes from Actuated to Not actuated. Go to step 6	Go to step 2
2	Check wiring for short circuit to B+	Switch off ignition. Pull plug A off rear convenience system control unit. Switch on ignition. Measure voltage between rear control module plug A, pin 3 and ground.	< 0.3 V Go to step 3	Check and if necessary repair pin 1 of the 6-pin connector in rear window area (right) and pin 2 of the 2-pin connector in rear window area (center right). Repair wiring. → End
3	Check wiring for short circuit to ground	Measure resistance between control module plug A pin 3 and ground.	∞ Ω Go to step 4	Check and if necessary repair pin 1 of the 6-pin connector in rear window area (right) and pin 2 of the 2-pin connector in rear window area (center right). Repair wiring. → End
4	Check wire from rear convenience system control module to rear window switch	Measure resistance between pin 3 of control module plug A and switch plug A2.	< 5 Ω Go to step 5	Check and if necessary repair pin 1 of the 6-pin connector in rear window area (right) and pin 2 of the 2-pin connector in rear window area (center right). Repair wiring. → End
5	Replace rear window switch (button)		→ End
6	Replace rear convenience system control module		→ End