C0387
Transfer Case Position Sensor
The transfer case control module has detected an implausible signal from the position sensor that reports the current shift position (2HI, 4HI, 4LO, neutral). Without a valid position the system cannot complete a range change.
- Check engine light: Not always
- Emissions related: No
- Repair difficulty: hard
Symptoms
- ABS warning light on
- ESC/stability control deactivated
- Possible reduced brake assist
- Speedometer may behave erratically
Common causes
Ordered by how often each turns out to be the cause.
- Transfer case position sensor failedCommon
- Wiring or connector faultPossible
- Encoder motor stuck between positionsLess likely
Parts involved
- Transfer Case Position Sensor
- Transfer Case Module
- Encoder Motor
C0387 is a generic OBD-II code defined by SAE J2012. Exact wording and diagnostic procedure vary by manufacturer and model. Code definitions are drawn from the public-domain OBDex dataset; the workshop notes are our own.