P2538Ignition Switch Accessory Position Circuit High
- Generic OBD-II code · Powertrain
- How the car detects it
- P2538 is set when the accessory input reads high in a state where it should be inactive, for instance once the vehicle is switched off and the body module should have released the line. Backfeed from an aftermarket device, a stuck accessory relay or a wire touching a battery feed are the obvious causes. A permanently high accessory line can keep modules awake and drain the battery. No manufacturer publishes P2538; the documented counterpart is GM's P2537, judged on the accessory wake-up signal against propulsion status, and GM's PIT5308 notes that some voltage after key-off is normal while the body module is still awake, so timing matters before calling the line faulty. P2536 is the general and P2537 the low fault.
- What you may notice
- Battery drain while parked
- Radio or accessories stay on after key-off
- Likely causes
- PossibleBackfeed from aftermarket equipment connected to the accessory line
- PossibleAccessory relay stuck closed
- RareAccessory wire chafed against a battery feed
- Repair
- Medium · Usually a job for a workshop.Typical cost: €20 – €400
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.