P0385Crankshaft Position Sensor B Circuit
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- Can trigger limp mode
- Needs a drive cycle to confirm a fix
- How the car detects it
- Some engines have a second crankshaft sensor or a second track on the tone wheel, which the engine module checks against sensor A or the camshaft. P0385 means its signal is missing or does not match. GM's 2004 Northstar 4.6 V8 counts the crank pulses per cam pulse (target 48 ± 1, fault in 8 of 10 tests) and also flags 2 s while cranking or 0.4 s running without a match, after two trips; an active P0385 suspends the cam sensor check. GM's 3.8-litre V6 (2006) sets it when its low resolution track stays silent while the medium resolution track delivers 36 pulses, 40 of 50 samples. The Honda 3.5-litre in the 2004 Saturn Vue Redline sets it when the second crank signal is missing while the first runs, judged after 17 revolutions, in the first trip. The engine usually keeps running on sensor A.
- What you may notice
- Check engine light on
- Longer cranking
- Tachometer flickers, rough running
- Rarely stalling
- Likely causes
- LikelyCrankshaft position sensor B faulty
- LikelyConnector or wiring open or corroded
- RareTone wheel or second track damaged
- RareEngine module
- Inspection (ITP)
- Matters for the ITP. While the check-engine light is on, the car fails the emissions check.
- Repair
- Medium · Often possible to do yourself.Typical cost: €60 – €350
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.