P2CA1Charge Air Cooler Coolant Pump Sense Circuit High
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- Can trigger limp mode
- How the car detects it
- Some electric pumps in a water-cooled charge air cooler loop report back to the engine computer on a dedicated sense or feedback wire, kept apart from the line commanding them. P2CA1 means the level on that return wire stays above its plausible band. Usual reasons are a chafed wire touching a battery feed, a break in the line where the controller input is pulled up internally, or pump electronics that no longer switch the line at all. The title carries no pump letter. No manufacturer documents P2CA1 publicly. Pierburg's patent US8392060B2 explains that such pumps announce faults by tying a line to ground for coded periods, so a line that never drops hides every message. CARB requires circuit checks on emission-related inputs. Unable to confirm the pump, the controller may cut boost.
- What you may notice
- MIL on
- Reduced power or boost under load, especially in hot weather
- Pump fault messages from the pump no longer reach the controller
- Likely causes
- LikelyFeedback wire chafed through and touching a battery or ignition feed
- PossibleBroken feedback wire or backed-out pin, input floats to its high level
- PossiblePump electronics no longer pulling the feedback line down
- RareDamaged input stage in the engine control module
- Inspection (ITP)
- Matters for the ITP. While the check-engine light is on, the car fails the emissions check.
- Repair
- Medium · Usually a job for a workshop.Typical cost: €40 – €600
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.