P23EFCamshaft B Position Signal Output Circuit/Open (Bank 2)
- Generic OBD-II code · Powertrain
- Can trigger limp mode
- How the car detects it
- P23EF covers the last combination of this series: camshaft B, usually the exhaust shaft, on bank 2, the cylinder bank without cylinder 1. On V-engines with four camshafts the ECM can provide a separate phase output per shaft, and P23EF says the bank 2 exhaust output has lost circuit continuity – a broken wire, a terminal backed out of its connector or a missing load at the receiving end. No manufacturer documents P23EF publicly. GM evaluates its comparable camshaft A outputs only with the engine not cranking and the powertrain relay at 11 V or more, and those faults do not turn on the MIL. Shorts are separated out as P23F0 (to ground) and P23F1 (to power); bank 1 has the same open-circuit check under P23EC.
- What you may notice
- Code stored without warning lamp on many vehicles
- Module relying on the signal sets its own fault codes
- Likely causes
- LikelyWire break in the bank 2 camshaft B output line
- PossibleTerminal backed out of the connector housing
- RareReceiving module disconnected or with failed input
- Repair
- Medium · Usually a job for a workshop.Typical cost: €50 – €900
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.