OBD-II code · Powertrain (generic, extended)
P25BA Regeneration Control Switch Circuit/Open
The DPF/SCR forced-regeneration request switch — used on commercial vehicles to let the operator force a parked regeneration when the automatic regen has been postponed too often — is open. The ECM cannot honour an operator request for forced regen.
Is it safe to drive with P25BA?
Usually safe to drive in the short term. Get it diagnosed when convenient, sooner if the car drives differently.
Common causes
- Most likelyOpen switch wire
- Less likelyPin pushed back out of connector body
- Less likelyCracked solder joint inside the module or sensor
Repair at a glance
- Difficulty
- Medium
- DIY friendly
- Often, with basic tools
- Typical labour
- 0.3–1.5 h
- Emissions test
- Likely to fail
- Parts involved
- Regen Request Switch, Wiring Harness
Related codes
- P25B7Auxiliary Ignition Switch On/Start Position Circuit
- P25B8Auxiliary Ignition Switch On/Start Position Circuit Low
- P25B9Auxiliary Ignition Switch On/Start Position Circuit High
- P25BBRegeneration Control Switch Circuit Low
- P25BCRegeneration Control Switch Circuit High
- P25BDUnmetered Fuel - Forced Engine Shutdown
Code data: OBDex open dataset (CC0). Labour times are typical ranges, not a quote.