Signal Missing

Signal missing

Checking the component and wiring
Check the fuse for the circuit.
Check the camshaft reset valve connector. Check for contact resistance. Check for oxidation.
Check the signal cable between engine control module (ECM) terminal #A72 (#B12) and camshaft reset valve terminal #2. Check for an open-circuit.
Check the power cable between camshaft reset valve terminal #1 and the system relay. Check for an open-circuit.

Hint: With the ignition switched on, the reading must be approximately 12 V between camshaft reset valve terminal #1 and ground.

Remedy as necessary.

Other information
- Connecting the breakout box, B5254T7 Connecting the Breakout Box, Engine Control Module (ECM)
- Signal specification, B5254T7 Signal Specification
- For information about fuses, see the wiring diagram
- VVT solenoid, B5254T7 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.




- Start the engine
- Read off the value for the camshaft closing angle and the desired value for the camshaft closing angle
- Active the quick test of camshaft control by clicking the start button
- Increase the engine speed (RPM) to approximately 2500 rpm and keep the engine running at this speed.
When the engine speed (RPM) increases, the control module will start the quick test to guide the camshaft to the different target values.
During the quick test, check that the closing angle of the camshaft (actual value) corresponds to the desired camshaft closing angle (target value) to an accuracy of ±10°. If the values do not correspond to an accuracy of ±10°, the function is faulty.
Deviation between the values can be read off in the lower display.
Carry out the check for approximately 15 seconds at an engine speed (RPM) of 2500 rpm. When the desired value is stable once again, the test has been completed. To restart the test, let the engine return to idle speed, then increase the engine speed to approximately 2500 rpm again.

Note! The test is active until the ignition is switched off. Switch off the ignition before the vehicle is delivered to the customer.





Is the function OK?

Yes - VERIFIED

No - VERIFICATION FAILED

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VERIFICATION FAILED - Fault-tracing information

VERIFIED - FAULT FOUND

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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 component and wiring

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