P0378: Timing Reference High Resolution Signal B Intermittent or Erratic Pulses
Do not keep driving
Expect intermittent roughness and power loss that varies with load. Report the conditions.
What this code means
An unstable pulse train on the second high-resolution reference. Mechanical causes lead — reluctor runout, or a sensor mounting that has loosened enough for the air gap to vary under load.
Likely causes
Start here
- Intermittent wiring fault · moderate
- Incorrect sensor air gap · moderate
- Damaged reluctor or tone ring · specialist
- Corroded or loose connector · easy
Symptoms
Components involved
Information, not instruction
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Community experience
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