Signal Missing

Signal missing

Checking the wiring








- Ignition off
- Disconnect the connector for the front mass movement sensor (MMS) or ultrasonic sensor (IMS).
Check the signal cables between the mass movement sensor (MMS) or ultrasonic sensor (IMS) and Central electronic module (CEM).

Note! When the adapter wiring cannot be used, take the reading on the reverse of the connector if possible in order not to damage the contacts. If the reading cannot be taken on the reverse, use a loose terminal pin to take the reading in the connector.

Take readings between:
- Central electronic module (CEM) terminal #H21 (#35) and mass movement sensor (MMS) or (IMS) #A1 for an open-circuit and short-circuit to voltage and ground.
- Central electronic module (CEM) terminal #H17 (#37) and rear mass movement sensor (MMS) or (IMS) #A3 for an open-circuit and short-circuit to voltage and ground.
- Central electronic module (CEM) terminal #D10 (#10) and movement sensor (MMS) or (IMS) #A5 for an open-circuit.
Remedy as necessary.
If no other fault is detected, replace the front movement sensor (MMS) or (IMS).

Other information
- Connecting the breakout box Connecting the Breakout Box, Central Electronic Module (CEM)
- Signal description Central Electronic Module (CEM) Signal Description, Central Electronic Module (CEM)
- Control module relay box passenger compartment Service and Repair
- Front intrusion sensor Removal and Replacement
- Checking wiring and terminals Checking Wiring and Terminals

Continue - Verification

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Verification




Verification

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








- Ignition off
- Reinstall the connectors, components etc.
Check the function of the mass movement sensor (MMS) as follows:

Note! Check that the function for reduced alarm is not activated before carrying out the check. If reduced alarm is activated, the car will not react to signals from the mass movement sensors (MMS).

- Open one of the side windows
- Lock the car using the remote control or a key
- Wait approximately 30 seconds until the alarm LED on the dashboard flashes briefly approximately once every 3 seconds.
- Insert your hand through the open window. Move your hand back and forth in the middle of the passenger compartment.
The alarm should be triggered.

Hint: To deactivate the alarm, press the unlocking button on the remote control

Is the alarm triggered?

Yes - VERIFIED

No - VERIFICATION FAILED

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VERIFIED - FAULT FOUND

VERIFICATION FAILED - Fault-tracing information

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Fault-tracing information




Information

Fault-tracing information
The fault should have been detected and remedied. As this is not the case fault-tracing has failed.
Exit fault-tracing for this diagnostic trouble code (DTC) or make another attempt.

Do you want to exit fault-tracing?

Yes - Exit fault-tracing

No - Attempt New Test

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Attempt New Test - Checking the wiring

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