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GLA-452




MA. DTC 452

Condition

Diagnostic trouble code (DTC) GLA-452 is stored is the control module registers that the signal from is greater than 5 V for 10 seconds after the alarm has been activated.

Substitute Value
None.

Possible Source
Short-circuit to supply voltage in the signal cable.

Fault Symptom(s)
The ultrasonic sensors receive no shut-oft signal
when airing the car is carried out, which can cause a false alarm

Start fault-tracing with MB.


MB1. Checking Signal From Airing Module





Ignition on.
Go into scrolling values.
Read off airing module status.
The value should be OFF.
Is the value OFF?
Yes: Go to MB4.
No: Go to MB2.


MB2. Checking Cables





Check cable between control module #A21 and airing module for a short-circuit to supply voltage according to WWA4 WW. Checking Wiring and Connections Then continue with MB3


MB3. Verification





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

Ignition on.
Reconnect connectors, reinstall components.
Go into scrolling values.
Read off airing module status.
The value should be OFF.
Is the value OFF?
Yes: Fault corrected
No: Fault not found


MB4. Intermittent





Check cable between control module #A21 and airing module #XX for an intermittent short-circuit to supply voltage according to WWB4 WW. Checking Wiring and Connections Operation done