Signal Missing

Signal missing

Checking the status




- Ignition on.
Activate the valve in the leak diagnostic unit to check whether the fault is permanent or intermittent.
The valve clicks when activated.
The fault is permanent if the valve does not activate.
The fault is intermittent if the valve activates.





Continue - Checking components and wiring

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Checking components and wiring
Check the fuse for the circuit.
Check the leak diagnostic unit connectors. Check for contact resistance and oxidation.
Check the resistance of the valve between the leak diagnostic pump connector terminals #3 and #4 (leak diagnostic unit side).
Check the signal cable between engine control module (ECM) terminal #B46 (#C46) and leak diagnostic pump terminal #3. Check for an open-circuit.
Check the power supply cable between system relay terminal #5 and leak diagnostic unit terminal #4. Check for an open-circuit.
Remedy as necessary.

Other information
- Connecting the breakout box, B5254T7 Connecting the Breakout Box, Engine Control Module (ECM)
- Signal specification, B5254T7 Signal Specification
- Component specifications, B5254T7 [1][2]Engine Control Module
- Leak diagnostic pump, B5254T7, AW55-50/51SN, B5254T7, M66 Service and Repair
- 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 on.
Activate the valve in the leak diagnostic unit.
The valve must click.





Is the function OK?

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 status

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