Pulse Width Modulation (PMW) Signal Too Low

2004 Volvo V70 L5-2.4L VIN 64 B5244S6SECTION Pulse Width Modulation (PMW) Signal Too Low





Pulse width modulation (PWM) signal too low

Checking components and wiring
Check the signal cable between Engine control module (ECM) #B25 (#B35) and accelerator pedal position sensor #2.
Check the power supply from the system relay to accelerator pedal (AP) position sensor terminal #1. Check the ground lead to accelerator pedal (AP) position sensor terminal #3.
Remedy as necessary.

Other information:
- To connect the breakout box, see Connecting the breakout box Connecting the Breakout Box
- For information about signals, see Signal specification Signal Description / Specification
- To access and replace the accelerator pedal (AP) position sensor, see Accelerator pedal (AP), replacing Service and Repair
- To fault-trace the wiring and terminals, see Checking wiring and terminals Checking Wiring And Terminals.






Continue - Verification

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Verification




Verification

Verification

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








- Ignition off
- Reinstall the connectors, components etc.
- Ignition on.
Activate the read off of the signals from the accelerator pedal (AP) position sensor.
Check that the value for both signals is approximately 8% when the accelerator pedal (AP) is unaffected and approximately 82% when the pedal is fully depressed.





Do the values correspond?

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 - FAULT-TRACING FAILED

No - Attempt New Test

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FAULT-TRACING FAILED - FAULT-TRACING FAILED

Attempt New Test - Checking components and wiring

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RENDER: 1.0x

NO RELATED

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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

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