Fault In Power Supply

Fault in power supply.

Erasing diagnostic trouble codes (DTCs)




- Ignition on.
Erase DTCs.






Continue - Reading off diagnostic trouble codes (DTCs)

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Reading off diagnostic trouble codes (DTCs)




- Ignition on.




- Wait at least 1 minute.
- Ignition off, remove the key from the ignition switch and close all doors, the hood, trunk lid or tailgate.
- Lock the car with the remote control.
- Wait for approximately 10 seconds.
- Unlock the car with the remote control.
- Ignition on.
- Read off diagnostic trouble codes (DTCs).

Did diagnostic trouble code (DTC) GLA-321 recur?

Yes - Checking connectors

No - Intermittent fault

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Checking connectors
- Ignition off.




- Expose VGLA control module according to Replacing main control module Replacing Main Control Module.
- Remove siren according to Replacing the siren Replacing the Siren.
Check siren and VGLA control module connectors for contact resistance and oxidation according to Checking wiring and terminals. Permanent fault Checking Wiring and Terminals. Permanent Fault.
- Ignition on.
- Erase DTCs.

Continue - Reading off diagnostic trouble codes (DTCs)

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Reading off diagnostic trouble codes (DTCs)




- Ignition on.




- Wait at least 1 minute.
- Ignition off, remove the key from the ignition switch and close all doors, the hood, trunk lid or tailgate.
- Lock the car with the remote control.
- Wait for approximately 10 seconds.
- Unlock the car with the remote control.
- Ignition on.
- Read off diagnostic trouble codes (DTCs).

Did diagnostic trouble code (DTC) GLA-321 recur?

Yes - Checking cables

No - FAULT FOUND

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Checking cables




- Ignition off.
Check fuse 6.

Hint: If the fuse is blown, check the circuit after fuse 6 for an open-circuit according to Checking wiring and terminals. Permanent fault Checking Wiring and Terminals. Permanent Fault.

Check cable between control module #B15 and siren #5 for a short-circuit to ground according to Checking wiring and terminals. Permanent fault Checking Wiring and Terminals. Permanent Fault and for an open-circuit according to Checking wiring and terminals. Permanent fault Checking Wiring and Terminals. Permanent Fault. Check cable between fuse 6 and siren #4 for an open-circuit according to Checking wiring and terminals. Permanent fault Checking Wiring and Terminals. Permanent Fault.

Other information:
- The voltage between siren #4 and ground should be battery voltage.
Remedy as necessary.










Continue - Erasing diagnostic trouble codes (DTCs)

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Erasing diagnostic trouble codes (DTCs)




- Ignition on.
Erase DTCs.






Continue - Verification

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Verification

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




- Reinstall connectors, components etc.
- Remove key from ignition switch
- Ensure that all doors, the hood and trunk lid are shut.
- 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-321 recur?

Yes - Fault-tracing information

No - FAULT FOUND

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Fault-tracing information
Verification indicates that the fault persists.

Do you want to repeat fault-tracing?

Yes - Erasing diagnostic trouble codes (DTCs)

No - No Fault Found

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Intermittent fault
Check cable between control module #B15 and siren #5 for an intermittent short-circuit to ground according to Checking wiring and terminals. Intermittent faults Checking Wiring and Terminals. Intermittent Faults and an intermittent open-circuit according to Checking wiring and terminals. Intermittent faults Checking Wiring and Terminals. Intermittent Faults. Check cable between fuse 6 and siren #4 for an intermittent open-circuit according to Checking wiring and terminals. Intermittent faults Checking Wiring and Terminals. Intermittent Faults.






Continue - Fault-tracing information

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Fault-tracing information
If the fault is intermittent, do not verify fault-tracing if the fault does not recur.

Do you want to repeat fault-tracing?

Yes - Erasing diagnostic trouble codes (DTCs)

No - No Fault Found

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