OBD-II code · Powertrain (generic)
P0393 Camshaft Position Sensor B Circuit High (Bank 2)
Cam sensor B on bank 2 above upper plausibility — open signal or short to B+. The camshaft position sensor identifies which cylinder is on the compression stroke — without it the ECM cannot run sequential injection or coil-on-plug ignition correctly.
Is it safe to drive with P0393?
Usually safe to drive in the short term. Get it diagnosed when convenient, sooner if the car drives differently.
Common causes
- Most likelyOpen signal line
- Less likelyConnector pins corroded - high contact resistance
- Less likelySupply wire pinched against B+ source
Symptoms
- Check engine light on
- Power loss especially in mid-rpm range
- Possible rough idle or stalling
- Increased fuel consumption
Repair at a glance
- Difficulty
- Medium
- DIY friendly
- Often, with basic tools
- Typical labour
- 0.5–2.5 h
- Emissions test
- Likely to fail
- Parts involved
- Camshaft Position Sensor
Related codes
- P0348Camshaft Position Sensor A Circuit High (Bank 2)
- P0368Camshaft Position Sensor B Circuit High (Bank 1)
- P0390Camshaft Position Sensor B Circuit (Bank 2)
- P0391Camshaft Position Sensor B Circuit Range/Performance (Bank 2)
- P0392Camshaft Position Sensor B Circuit Low (Bank 2)
- P0394Camshaft Position Sensor B Circuit Intermittent (Bank 2)
- P0395Cylinder 1 Pressure Sensor Circuit
- P0396Cylinder 1 Pressure Sensor Circuit Range/Performance
Code data: OBDex open dataset (CC0). Labour times are typical ranges, not a quote.