P05BCStop-Start Mode Switch Circuit/Open
- 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. P05BC means the switch circuit is open. No manufacturer document available to us uses this code; Stellantis documents only its sibling P05BD. Typical are a connector left off after console or dashboard work or an open switch contact.
- What you may notice
- Stop-start cannot be switched off or stays disabled
- Switch indicator not working
- Usually no check engine light
- Likely causes
- LikelyOpen circuit in switch, connector or wire
- PossibleSwitch faulty (contact or resistor ladder)
- PossibleConnector not refitted after console or dashboard work
- RareReading module or software
- 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.