OBD-II code · Powertrain (generic, extended)
P234C Cylinder 9 Pressure Sensor Circuit Intermittent or Erratic
Cylinder 9 pressure sensor signal jumps or drops out intermittently — connector or wiring issue. Wiring faults of this kind typically come from chafing, water ingress at connector seals, or pin push-back — a wiggle test on the harness while the code is active often confirms the location.
Is it safe to drive with P234C?
Usually safe for short trips, but don’t ignore it: the underlying fault can get more expensive over time.
Common causes
- Most likelyIntermittent contact at connector or terminal
- PossibleHarness chafed - intermittent short
- Less likelyConnector with intermittent contact under vibration
Repair at a glance
- Difficulty
- Hard
- DIY friendly
- Best left to a mechanic
- Typical labour
- 1.5–5 h
- Emissions test
- Likely to fail
- Parts involved
- Cylinder Pressure Sensor 9, Cylinder Pressure Wiring 9
Related codes
- P2356Cylinder 10 Pressure Sensor Circuit Intermittent or Erratic
- P2360Cylinder 11 Pressure Sensor Circuit Intermittent or Erratic
- P236ACylinder 12 Pressure Sensor Circuit Intermittent or Erratic
- P2349Cylinder 9 Pressure Sensor Circuit Range/Performance
- P234ACylinder 9 Pressure Sensor Circuit Low
- P234BCylinder 9 Pressure Sensor Circuit High
- P234DCylinder 9 Pressure Too Low
- P234ECylinder 9 Pressure Too High
- P234FCylinder 9 Pressure Variation Low
Code data: OBDex open dataset (CC0). Labour times are typical ranges, not a quote.