P0855: Drive Switch Input Circuit High
What to do
Expect the idle to dip, and possibly stall, when you select drive or reverse. The engine itself is fine; it simply is not being told to expect the load.
What this code means
The drive selection signal reads above its valid range — an open circuit or a short to supply, read as drive never being selected. Idle compensation is therefore never applied, and the engine dips each time a gear is engaged.
Likely causes
Start here
- Open circuit in switch wiring · moderate
- Corroded or loose connector · easy
- Faulty transmission range sensor · moderate
Less common
- Wiring shorted to voltage · moderate
Symptoms
Components involved
Information, not instruction
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Have anything you intend to act on checked by a trained person against the manufacturer's own procedure for your vehicle. Nothing here replaces that procedure.
Community experience
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