P2505ECM/PCM Power Input Signal
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- Needs a drive cycle to confirm a fix
- How the car detects it
- P2505 covers the supply inputs of the engine module in general. GM documents it in the 2014 diesel engine table 14OBDG04: the module checks its permanent battery feed, the line that keeps the engine-off timer alive while the ignition is off. If that constant supply was interrupted, the module flags P2505 as soon as the ignition is on; a single event is enough, the test is evaluated a single time per trip and the code is GM type B, so the MIL follows on the second failing trip. Without that feed the module cannot know how long the engine was off, which other diagnostics rely on. Ford lists P2505 without MIL marker for the 2014 BOSS 302S. P2506 to P2509 narrow the fault to plausibility, low, high and intermittent.
- What you may notice
- MIL after two trips (GM)
- Often no drivability complaint
- Learned values may be lost
- Likely causes
- LikelyBattery disconnected or permanent-feed fuse removed or blown
- PossibleOpen or corroded permanent supply wire or connector
- RareSupply monitoring inside the module defective
- 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: €10 – €400
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.