P05BFStop-Start Mode Switch Circuit High
- Generic OBD-II code · Powertrain
- How the car detects it
- The stop-start off switch lets the driver disable automatic engine stop for the current drive. It is read directly or via another module over CAN – on Stellantis' 2025 Ram 1500 it sits in the electronic shifter module. CARB names a stop-start diagnosis as its example of an emission-neutral diagnosis, so no warning lamp is required; stop-start is usually just disabled. P05BF means the switch circuit voltage is too high – a short to positive or, with a pull-up, a missing switch ground. No manufacturer document available to us uses this code.
- What you may notice
- Stop-start cannot be switched off or stays disabled
- Switch indicator not working
- Usually no check engine light
- Likely causes
- LikelySignal line shorted to positive
- PossibleSwitch ground open (signal pulled up)
- PossibleSwitch faulty
- RareModule input
- Repair
- Easy · Often possible to do yourself.Typical cost: €30 – €200
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.