Z. Checking Door Lock Switch, Front Door

ZA. Fault Tracing


Condition
No diagnostic trouble codes (DTCs) stored.

Possible Source
Open-circuit in signal cables from door lock switch.
Open-circuit in door lock switch ground lead
Fault in door lock switch in driver's door lock unit.

Start fault-tracing with ZB.


ZB1. Checking Locking Signal From The Door Lock Switch





Ignition on.
Go into scrolling values.
Turn the key to the locking position.
Read oft the status of the door lock switch in the driver's door.
The value should be LOW.

NOTE: A diagnostic trouble code (DTC) is stored if the key is held in the locking position for more than 10 seconds.

Is the value LOW?
Yes: Go to ZB5.
No: Go to ZB2.


ZB2. Checking Contact Resistance


Expose driver's door lock unit.
Check VGLA control module and gray lock unit connector for contact resistance and oxidation according to WWA5 WW. Checking Wiring and Connections
Ignition on.
Go into scrolling values.
Turn the key to the locking position.
Read off the status of the door lock switch in the driver's door.
The value should be LOW when the key is turned to the locking position.


NOTE: A diagnostic trouble code (DTC) is stored if the key is held in the locking position for more than 10 seconds.


If the value is OK the cause of the fault has been loose connections in the connectors.
Is the value LOW?
Yes: Fault corrected
No: Go to ZB3.


ZB3. Checking Cables





For left-hand drive cars:
Check cable between VGLA control module #A16 and gray lock unit connector terminal 2 and the cable between gray lock unit connector terminal 3 and ground for an open-circuit according to WWA2 WW. Checking Wiring and Connections

For right-hand drive cars:
Check cable between VGLA control module #A16 and gray lock unit connector terminal 3 and gray lock unit connector terminal 2 and ground for an open-circuit according to WWA2 WW. Checking Wiring and Connections

Were any faults found in the cables?
Yes: Go to ZB9.
No: Go to ZB4.


ZB4. Replacing Component

Replace lock unit.
Then continue with ZB9


ZB5. Checking Unlocking Signal From Door Lock Switch





Ignition on.
Go into scrolling values.
Turn the key to the unlocking position.
Read off the status of the door lock switch in the driver's door.
The value should be LOW when the key is turned to the unlocking position.

NOTE: A diagnostic trouble code (DTC) is stored if the key is held in the unlocking position for more than 10 seconds.

Is the value LOW?
Yes: Fault not found
No: Go to ZB6.

ZB6. Checking Contact Resistance





Expose driver's door lock unit.
Check VGLA control module connector and gray lock unit connector for contact resistance and oxidation according to WWA5 WW. Checking Wiring and Connections
Ignition on.
Go into scrolling values.
Turn the key to the unlocking position. Read off the status of the door lock switch in the driver's door.
The value should be LOW when the key is turned to the unlocking position.

NOTE: A diagnostic trouble code (DTC) is stored if the key is held in the unlocking position for more than 10 seconds.

If the value is OK the cause of the fault has been loose connections in the connectors.
Is the value LOW?
Yes: Fault corrected
No: Go to ZB7.

ZB7. Checking Cables





For left-hand drive cars:
Check cable between VGLA control module #A18 and gray lock unit connector terminal 1 for an open-circuit according to WWA2 WW. Checking Wiring and Connections

For right-hand drive cars:
Check cable between VGLA control module #A18 and gray lock unit connector terminal 4 for an open-circuit according to WWA2 WW. Checking Wiring and Connections

Were any faults found in the cable?
Yes: Go to ZB9.
No: Go to ZB8.


ZB8. Replacing Component

Replace driver's door lock unit. Replacing door lock units in Body and Frame.
Then continue with ZB9

ZB9. Verification





Hint: After carrying out the repair check that the fault has been remedied.

Ignition off.
Reconnect connectors, reinstall components.
Ignition on.
Go into scrolling values.
Turn the key to the locking position and then to the unlocking position.
Read off the door lock switch status.
The value should be LOW.
Is the value LOW?
Yes: Fault corrected
No: Fault not found