P2CE9Particulate Filter Pressure Sensor C Circuit Intermittent/Erratic
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- How the car detects it
- P2CE9 catches a sensor C signal that jumps rather than drifts. GM's 2025 diesel tables call this a quick change check: when two consecutive raw samples of the downstream relative pressure sensor differ by more than 20 %, the sample counts as failed, and 99 failures in 200 samples set a Type B code. The test is suspended while cranking and whenever an electrical low or high fault is already present, so it really targets short dropouts. Ford's 2024–25 petrol summary lists P2CE9 within its continuous analog circuit check for gasoline particulate filters, with about 5 s to register and no separate threshold published. Loose terminals that open under engine vibration, a harness rubbing on a bracket or moisture entering the connector are the usual finds; wiggling the harness during live data helps. Sensor D uses P2CEE.
- What you may notice
- Warning lamp on, sometimes after rough roads or rain
- Pressure value jumps in live data
- Fault may disappear and return
- Likely causes
- LikelyLoose or corroded terminal in the sensor C connector
- PossibleHarness rubbing through on a bracket or exhaust part
- PossibleWater entering the connector intermittently
- RareIntermittent internal fault of the sensor
- 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: €20 – €300
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.