Operation CHARM: Car repair manuals for everyone.

Comparison Fault






Comparison fault

Fault-tracing information
Check and remedy any diagnostic trouble codes (DTCs) in the central electronic module (CEM) before fault-tracing this diagnostic trouble code (DTC).

Note! The analog accelerator pedal (AP) position sensor signal is transmitted from the central electronic module (CEM) via CAN communication to the engine control module (ECM).

Remedy as necessary.


Continue - Checking the status

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Checking the status




- Ignition on
- Read off the movement of the accelerator pedal by carefully depressing and releasing the accelerator pedal (AP).
Check that the values for the PWM signal and the analog signal change with accelerator pedal movement. The values must follow each other and be between 5 % (released pedal) and a maximum of 90 % (fully depressed pedal). The function is OK if the values are within this range and follow each other with the pedal movement.
The fault is intermittent at the moment if the function is OK.






Continue - Checking the power supply

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Checking the power supply




- Ignition on.
Check the power supply (12 V) to the accelerator pedal (AP) position sensor between accelerator pedal (AP) position sensor terminals #4 (wiring side) and #6 (wiring side).
Check that the power supply is approximately 12 V with the ignition on.

Other information
- Connecting the breakout box Connecting The Breakout Box, Engine Control Module (ECM)
- Signal specification Signal Specification, Engine Control Module (ECM)
- Accelerator pedal Accelerator Pedal
- Checking wiring and terminals Checking Wiring and Terminals













Is the power supply OK?

Yes - Checking the connectors and cables

No - Checking the component and wiring

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Checking the connectors and cables




- Ignition off.
Check the signal cable between engine control module (ECM) terminal #B26 (#C26) and accelerator pedal (AP) position sensor terminal #5 (wiring side). Check for an open-circuit. Check for a short-circuit to ground. Check for a short-circuit to supply voltage.
Try a new accelerator pedal (AP) position sensor if no fault is found and the fault is permanent.
Remedy as necessary.

Other information
- Connecting the breakout box Connecting The Breakout Box, Engine Control Module (ECM)
- Signal specification Signal Specification, Engine Control Module (ECM)
- Accelerator pedal Accelerator Pedal
- Checking wiring and terminals Checking Wiring and Terminals














Continue - Verification

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Checking the component and wiring




- Ignition off
- Check the accelerator pedal (AP) position sensor connector. Check for contact resistance and oxidation.
Check the power supply cable (12 V) between accelerator pedal (AP) position sensor terminal #6 (wiring side) and the relevant fuse for the circuit. Check for a short-circuit to ground. Check for an open-circuit. Check that the fuse for the circuit is not damaged.
Check the ground lead for power supply (12 V) between accelerator pedal (AP) position sensor terminal #4 (wiring side) and the relevant ground terminal. Check for contact resistance and oxidation. Check for an open-circuit.

Hint: With the ignition on, the power supply to the accelerator pedal (AP) position sensor must be approximately 12 V measured between accelerator pedal (AP) position sensor terminals #4 (wiring side) and #6 (wiring side).

Remedy as necessary.

Other information
- Connecting the breakout box Connecting The Breakout Box, Engine Control Module (ECM)
- Signal specification Signal Specification, Engine Control Module (ECM)
- For further information about the fuses and relays, see the Wiring Diagram
- Accelerator pedal Accelerator Pedal
- Checking wiring and terminals Checking Wiring and Terminals














Continue - Checking the connectors and cables

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Verification




Verification

Verification

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








- Ignition off
- Reconnect the connectors, reinstall components etc.
- Ignition on.
Read off the movement of the accelerator pedal by carefully depressing and releasing the accelerator pedal (AP).
Check that the values for the PWM signal and the analog signal change with accelerator pedal movement. The values must follow each other and be between 5 % (released pedal) and a maximum of 90 % (fully depressed pedal). The function is OK if the values are within this range and follow each other with the pedal movement.
The fault has been remedied if the function is OK.





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 - Fault-tracing information

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