P2C40Fan 4 Control Circuit High
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- How the car detects it
- P2C40 states that fan control output 4 is held at too high a level: the line has contact with battery voltage, or the driver cannot pull it down when it should. In Saab's 2011 9-5 the counterpart relay codes P0692, P0694 and P0696 stand for a relay control wire shorted to a voltage source, and the manual adds that a stage stuck on can also occur without any stored code. No manufacturer publicly documents P2C40. Typical finds are insulation worn through against a live wire, moisture bridging two pins and a defective relay or fan module input. The fan may run without pause, even after the engine is off, or not respond at all, and a fan that keeps turning can flatten the 12 V battery. Low voltage is P2C3F, the general circuit fault P2C3E.
- What you may notice
- Fan 4 runs constantly, sometimes after switch-off
- Discharged 12 V battery after standing
- Check engine light
- Likely causes
- LikelyFan 4 control wire in contact with a battery-voltage circuit
- PossibleRelay or fan module input failed internally
- RareMoisture bridging pins in the connector
- 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 – €400
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.