P0388: Crankshaft Position Sensor B Circuit High
Do not keep driving
Expect reduced performance. Diagnose rather than driving at length.
What this code means
The second crankshaft signal is above its valid range — a short to supply, or an open ground letting the input float.
Likely causes
Start here
- Wiring shorted to voltage · moderate
- Open sensor ground circuit · moderate
- Faulty crankshaft position sensor · moderate
Less common
- Corroded or loose connector · easy
Symptoms
Components involved
Information, not instruction
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Community experience
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