Part 2

Signal too low. Intermittent fault (Continued)

Checking the locking motor wires
Check door control unit and lock unit connectors for contact resistance and oxidation as described in Checking wiring and terminals. Permanent fault Checking Wiring and Terminals. Permanent Fault.
Trouble-shoot the wire between door control unit connector B2 and lock unit connector 8 for an open circuit as described in Checking wiring and terminals. Permanent fault Checking Wiring and Terminals. Permanent Fault.
Trouble-shoot the wire between door control unit connector B6 and lock unit connector 7 for an open circuit as described in Checking wiring and terminals. Permanent fault Checking Wiring and Terminals. Permanent Fault.

Additional information
- To access/replace rear electronic module (REM), see Integrated relay/fusebox cargo compartment/Rear electronic module (REM), replacing Integrated Relay/Fusebox Cargo Compartment/Rear Electronic Module (REM), Replacing.





Is there a fault?

Yes - Fault Found

No - Replacing the component

------------------------

Replacing the component
Replace lock unit as described in Replacing the switch for the lock unit / cargo compartment lighting Service and Repair.

Is there a fault?

Yes - Fault Found

No - Replacing the component

------------------------

Replacing the component
Replace control unit as described in Integrated relay/fusebox cargo compartment/Rear electronic module (REM), replacing Integrated Relay/Fusebox Cargo Compartment/Rear Electronic Module (REM), Replacing.


Continue - Fault Found

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FAULT FOUND - Fault Found

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Rear left door




Checking the rear left door

Check

Is the lock to the other rear door not working?

Yes - Checking the fuse

No - Replacing the component

------------------------

Replacing the component
Replace the relays for locking (2/111) and unlocking (2/112) in the boot relay/fuse box. At the same time check relay socket contacts for contact resistance and oxidation as described in Checking wiring and terminals. Permanent fault Checking Wiring and Terminals. Permanent Fault.

Additional information
- To access relay/fuse box in the boot, see Integrated relay/fusebox cargo compartment/Rear electronic module (REM), replacing Integrated Relay/Fusebox Cargo Compartment/Rear Electronic Module (REM), Replacing.









Is there a fault?

Yes - Fault Found

No - Circuit test

------------------------

Circuit test
The fault is caused by an open circuit in one of the relay circuits or in the lock unit. To find out which circuit contains the fault:
Disconnect the lock unit connector.
Check the contacts for contact resistance and oxidation as described in Checking wiring and terminals. Permanent fault Checking Wiring and Terminals. Permanent Fault.
Check resistance between 4 and 6 on cable connector.

Additional information
- To access/replace the lock unit, see appropriate service procedure.









The ohmmeter should display 0 ohm.

OK - Checking the components

Not OK - continued

------------------------

Circuit test, continued
Check the resistance between 4 and ground and between 6 and ground on the cable connector.
The ohmmeter should display 0 ohm.
1. The ohmmeter shows a fault between 4 and ground
2. The ohmmeter shows a fault between 6 and ground.









Choose the correct option from above.

1 - Checking the unlocking relay circuit

2 - Checking the locking relay circuit

------------------------

Checking the locking relay circuit
Remove the locking relay (2/111).
Check the wire between 4 in the cable connector and 3 in the relay socket for an open circuit as described in Checking wiring and terminals. Permanent fault Checking Wiring and Terminals. Permanent Fault.
If a fault is detected, check in particular the intermediate connector in the cable harness (2) for contact resistance and oxidation as described in Checking wiring and terminals. Permanent fault Checking Wiring and Terminals. Permanent Fault.
Do the necessary corrective action.
If no fault is found, check the resistance between 4 in the relay socket and ground.
The ohmmeter should display 0 ohm.
If the resistance deviates, replace the rear electronic module (REM).

Additional information
- To access/replace rear electronic module (REM), see Integrated relay/fusebox cargo compartment/Rear electronic module (REM), replacing Integrated Relay/Fusebox Cargo Compartment/Rear Electronic Module (REM), Replacing.














Continue - Fault Found

------------------------

Checking the unlocking relay circuit
Remove the unlocking relay (2/112).
Check the wire between 6 in the cable connector and 3 in the relay socket for an open circuit as described in Checking wiring and terminals. Permanent fault Checking Wiring and Terminals. Permanent Fault.
If a fault is detected, check in particular the intermediate connector in the cable harness (2) for contact resistance and oxidation as described in Checking wiring and terminals. Permanent fault Checking Wiring and Terminals. Permanent Fault.
Do the necessary corrective action.
If no fault is found, check the resistance between 4 in the relay socket and ground.
The ohmmeter should display 0 ohm.
If the resistance deviates, replace the rear electronic module (REM).

Additional information
- To access/replace rear electronic module (REM), see Integrated relay/fusebox cargo compartment/Rear electronic module (REM), replacing Integrated Relay/Fusebox Cargo Compartment/Rear Electronic Module (REM), Replacing.














Continue - Fault Found

------------------------

Checking the components
Check the resistance between pin 4 and 6 in the lock unit chassis contact.
The ohmmeter should display 5 ohm.
If the resistance deviates, replace the lock unit.

Additional information
- To access rear electronic module (REM), see Integrated relay/fusebox cargo compartment/Rear electronic module (REM), replacing Integrated Relay/Fusebox Cargo Compartment/Rear Electronic Module (REM), Replacing
- To access/replace the lock unit, see
- For information on signals and additional values, see Signal specification Pinout Values and Diagnostic Parameters.









Is there a fault?

Yes - Fault Found

No - Checking the relay supply

------------------------

Checking the relay supply
Remove the locking relay (2/111).
Measure the voltage between 5 in the relay socket and ground.
The voltmeter should display battery voltage.

Hint: If the value is OK but the fault still remains, connect the contacts to the lock module and link between 3 and 5 in the relay socket to force-feed the lock motor while continuing to test.

Additional information
- To access rear electronic module (REM), see Integrated relay/fusebox cargo compartment/Rear electronic module (REM), replacing Integrated Relay/Fusebox Cargo Compartment/Rear Electronic Module (REM), Replacing.









Does the voltmeter show the battery voltage?

Yes - Fault Found

No - Checking the fuse

------------------------

Checking the fuse
Remove the fuse 11D/8 in boot fuse box.
Check that fuse 11D/8 is intact and check for contact resistance and oxidation as described in Checking wiring and terminals. Permanent fault Checking Wiring and Terminals. Permanent Fault.

Additional information
- To access rear electronic module (REM), see Integrated relay/fusebox cargo compartment/Rear electronic module (REM), replacing Integrated Relay/Fusebox Cargo Compartment/Rear Electronic Module (REM), Replacing.









Is the fuse intact?

Yes - Checking for an open circuit

No - Checking for a short circuit

------------------------

Checking for an open circuit
Remove relay 2/111 in the rear electronic module (REM) and trouble-shoot the wire between the fuse holder secondary side (left) and 5 in the relay socket for an open circuit as described in Checking wiring and terminals. Permanent fault Checking Wiring and Terminals. Permanent Fault.

Additional information
- To access rear electronic module (REM), see Integrated relay/fusebox cargo compartment/Rear electronic module (REM), replacing Integrated Relay/Fusebox Cargo Compartment/Rear Electronic Module (REM), Replacing.










Continue - Fault Found

------------------------

Checking for a short circuit
Check the resistance between the fuse holder secondary side (left) and ground.
The ohmmeter should display infinite resistance.
If the value is correct, replace the fuse.
If the value deviates, trouble-shoot all the relay circuits involved for a short circuit to ground as described in Checking wiring and terminals. Permanent fault Checking Wiring and Terminals. Permanent Fault.

Hint: Replace fuse.
If the fuse works straight away the fault is a short circuit on the relay supply wire.
If the fuse works when activating each relay the short circuit is on the component supply wire
The relay circuits involved belong to relays 2/111, 2/112, 2/113, 2/114, 2/115, 2/56, 2/59 and 2/67.

Additional information
- To access rear electronic module (REM), see Integrated relay/fusebox cargo compartment/Rear electronic module (REM), replacing Integrated Relay/Fusebox Cargo Compartment/Rear Electronic Module (REM), Replacing.










Continue - Fault Found

------------------------

FAULT FOUND - Fault Found

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Rear right door




Checking the rear right door

Check

Is the lock to the other rear door not working?

Yes - Checking the fuse

No - Replacing the component

------------------------

Replacing the component
Replace the relays for locking (2/113) and unlocking (2/114) in the boot relay/fuse box. At the same time check relay socket contacts for contact resistance and oxidation as described in Checking wiring and terminals. Permanent fault Checking Wiring and Terminals. Permanent Fault.

Additional information
- To access relay/fuse box in the boot, see Integrated relay/fusebox cargo compartment/Rear electronic module (REM), replacing Integrated Relay/Fusebox Cargo Compartment/Rear Electronic Module (REM), Replacing.









Is there a fault?

Yes - Fault Found

No - Circuit test

------------------------

Circuit test
The fault is caused by an open circuit in one of the relay circuits or in the lock unit. To find out which circuit contains the fault:
Disconnect the lock unit connector.
Check the contacts for contact resistance and oxidation as described in Checking wiring and terminals. Permanent fault Checking Wiring and Terminals. Permanent Fault.
Check resistance between 4 and 6 on cable connector.

Additional information
- To access/replace the lock unit, see appropriate service procedure.









The ohmmeter should display 0 ohm.

OK - Checking the components

Not OK - continued

------------------------

Circuit test, continued
Check the resistance between 4 and ground and between 6 and ground on the cable connector.
The ohmmeter should display 0 ohm.
1. The ohmmeter shows a fault between 4 and ground
2. The ohmmeter shows a fault between 6 and ground.









Choose the correct option from above.

1 - Checking the unlocking relay circuit

2 - Checking the locking relay circuit

------------------------

Checking the locking relay circuit
Remove the locking relay (2/113).
Check the wire between 4 in the cable connector and 3 in the relay socket for an open circuit as described in Checking wiring and terminals. Permanent fault Checking Wiring and Terminals. Permanent Fault.
If a fault is detected, check in particular the intermediate connector in the cable harness (2) for contact resistance and oxidation as described in Checking wiring and terminals. Permanent fault Checking Wiring and Terminals. Permanent Fault.
Do the necessary corrective action.
If no fault is found, check the resistance between 4 in the relay socket and ground.
The ohmmeter should display 0 ohm.
If the resistance deviates, replace the rear electronic module (REM).

Additional information
- To access/replace rear electronic module (REM), see Integrated relay/fusebox cargo compartment/Rear electronic module (REM), replacing Integrated Relay/Fusebox Cargo Compartment/Rear Electronic Module (REM), Replacing.














Continue - Fault Found

------------------------

Checking the unlocking relay circuit
Remove the unlocking relay (2/114).
Check the wire between 6 in the cable connector and 3 in the relay socket for an open circuit as described in Checking wiring and terminals. Permanent fault Checking Wiring and Terminals. Permanent Fault.
If a fault is detected, check in particular the intermediate connector in the cable harness (2) for contact resistance and oxidation as described in Checking wiring and terminals. Permanent fault Checking Wiring and Terminals. Permanent Fault.
Do the necessary corrective action.
If no fault is found, check the resistance between 4 in the relay socket and ground.
The ohmmeter should display 0 ohm.
If the resistance deviates, replace the rear electronic module (REM).

Additional information
- To access/replace rear electronic module (REM), see Integrated relay/fusebox cargo compartment/Rear electronic module (REM), replacing Integrated Relay/Fusebox Cargo Compartment/Rear Electronic Module (REM), Replacing.














Continue - Fault Found

------------------------

Checking the components
Check the resistance between pin 4 and 6 in the lock unit chassis contact.
The ohmmeter should display 5 ohm.
If the resistance deviates, replace the lock unit.

Additional information
- To access rear electronic module (REM), see Integrated relay/fusebox cargo compartment/Rear electronic module (REM), replacing Integrated Relay/Fusebox Cargo Compartment/Rear Electronic Module (REM), Replacing
- To access/replace the lock unit, see
- For information on signals and additional values, see Signal specification Pinout Values and Diagnostic Parameters.









Is there a fault?

Yes - Fault Found

No - Checking the relay supply

------------------------

Checking the relay supply
Remove the locking relay (2/113).
Measure the voltage between 5 in the relay socket and ground.
The voltmeter should display battery voltage.

Hint: If the value is OK but the fault still remains, connect the contacts to the lock module and link between 3 and 5 in the relay socket to force-feed the lock motor while continuing to test.

Additional information
- To access relay/fuse box in the boot, see Integrated relay/fusebox cargo compartment/Rear electronic module (REM), replacing Integrated Relay/Fusebox Cargo Compartment/Rear Electronic Module (REM), Replacing.









Does the voltmeter show the battery voltage?

Yes - Fault Found

No - Checking the fuse

------------------------

Checking the fuse
Remove the fuse 11D/8 in boot fuse box.
Check that fuse 11D/8 is intact and check for contact resistance and oxidation as described in Checking wiring and terminals. Permanent fault Checking Wiring and Terminals. Permanent Fault.

Additional information
- To access relay/fuse box in the boot, see Integrated relay/fusebox cargo compartment/Rear electronic module (REM), replacing Integrated Relay/Fusebox Cargo Compartment/Rear Electronic Module (REM), Replacing.









Is the fuse intact?

Yes - Checking for an open circuit

No - Checking for a short circuit

------------------------

Checking for an open circuit
Remove relay 2/113 in the boot relay/fuse box and trouble-shoot the wire between the fuse holder secondary side (left) and 5 in the relay socket for an open circuit as described in Checking wiring and terminals. Permanent fault Checking Wiring and Terminals. Permanent Fault.

Additional information
- To access relay/fuse box in the boot, see Integrated relay/fusebox cargo compartment/Rear electronic module (REM), replacing Integrated Relay/Fusebox Cargo Compartment/Rear Electronic Module (REM), Replacing.










Continue - Fault Found

------------------------

Checking for a short circuit
Check the resistance between the fuse holder secondary side (left) and ground.
The ohmmeter should display infinite resistance.
If the value is correct, replace the fuse.
If the value deviates, trouble-shoot all the relay circuits involved for a short circuit to ground as described in Checking wiring and terminals. Permanent fault Checking Wiring and Terminals. Permanent Fault.

Note! If the value is correct the fault could be intermittent.

Hint: Replace fuse.
If the fuse works straight away the fault is a short circuit on the relay supply wire.
If the fuse works when activating each relay the short circuit is on the component supply wire
The relay circuits involved belong to relays 2/111, 2/112, 2/113, 2/114, 2/115, 2/56, 2/59 and 2/67.

Additional information
- To access relay/fuse box in the boot, see Integrated relay/fusebox cargo compartment/Rear electronic module (REM), replacing Integrated Relay/Fusebox Cargo Compartment/Rear Electronic Module (REM), Replacing.










Continue - Fault Found

------------------------

FAULT FOUND - Fault Found

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FAULT FOUND - DONE

No Fault Found - DONE

DONE - DONE

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