OBD-II code · Powertrain (generic)
P05BC Stop-Start Mode Switch Circuit Open
The driver-controlled switch that disables stop-start has an open control circuit - the ECU cannot read the driver preference and falls back to the default mode.
Is it safe to drive with P05BC?
Usually safe to drive in the short term. Get it diagnosed when convenient, sooner if the car drives differently.
Common causes
- Most likelyOpen in switch or harness
- Less likelyPin pushed back out of connector body
- Less likelyCracked solder joint inside the module or sensor
Repair at a glance
- Difficulty
- Easy
- DIY friendly
- Often, with basic tools
- Typical labour
- 0.3–1.2 h
- Emissions test
- Usually unaffected
- Parts involved
- Stop Start Switch
Code data: OBDex open dataset (CC0). Labour times are typical ranges, not a quote.