GLA-422

IA. DTC 422






Condition


Diagnostic trouble code (DTC) GLA-422 is stored after approximately 2 seconds it the control module registers a fault in the glass breakage sensor microphone or if communication between the microphone and internal control module is faulty when the alarm system is powered up or the alarm is activated or deactivated.

Substitute Value
None.

Possible Source
Fault in communication between microphone and glass breakage sensor control module

Fault Symptom(s)
The indicator LED in the sun sensor flashes for 15 seconds when the ignition is switched on.
The system will not trigger the alarm if there is glass breakage in the passenger compartment

Start fault-tracing with IB.


IB1. Erasing Diagnostic Trouble Codes (DTCs)





Ignition on.
Erase diagnostic trouble codes (DTCs).
Then continue with IB2.

IB2. Reading Off Diagnostic Trouble Codes (DTCs)

Remove key from ignition switch.
Ensure that all doors, the hood, trunk lid/tailgate are closed.
Lock the car with the remote control.
Wait approximately 10 seconds.
Unlock the car with the remote control.
Ignition on.
Read off diagnostic trouble codes (DTCs).
Does diagnostic trouble code (DTC) GLA-422 recur?
Yes: Go to IB8.
No: Go to IB3.


IB3. Checking Connectors

Ignition off.
Remove passenger side loudspeaker grille on dash board.
Check microphone connector for contact resistance and oxidation according to WWA5 WW. Checking Wiring and Connections
Ignition on.
Erase diagnostic trouble codes (DTCs).
Then continue with IB4.


IB4. Reading Off Diagnostic Trouble Codes (DTCs)

Remove key from ignition switch.
Ensure that all doors, the hood, trunk lid/tailgate are closed.
Lock the car with the remote control.
Wait approximately 10 seconds.
Unlock the car with the remote control.
Ignition on.
Read off diagnostic trouble codes (DTCs).
Does diagnostic trouble code (DTC) GLA-422 recur?
No: Fault corrected
Yes: Go to IB5.


IB5. Replacing Component

Try a new glass breakage sensor microphone.
Then continue with Go to IB6.


IB6. Erasing Diagnostic Trouble Codes (DTCs)

Ignition on.
Erase diagnostic trouble codes (DTCs).
Then continue with IB7.


IB7. Verification





Hint: After carrying out the repair, check that the fault has been remedied as follows:

Ignition off.
Reconnect connectors, reinstall components.
Remove the key.
Ensure that all doors, the hood, trunk lid/tailgate are closed.
Lock the car with the remote control.
Wait approximately 10 seconds.
Unlock the car with the remote control.
Ignition on.
Read off diagnostic trouble codes (DTCs).
Does diagnostic trouble code (DTC) GLA-422 recur?
Yes: Fault not found
No: Fault corrected

IB8. Intermittent Fault





Ignition off.
Remove passenger side loudspeaker grille on dashboard.
Check microphone connector for contact resistance and oxidation according to WWA5 WW. Checking Wiring and Connections Operation done