What does code P25BC mean?

Q: What does code P25BC mean?

Regeneration Control Switch Circuit High. P25BC indicates that the powertrain control module (PCM) has detected an abnormally high voltage on the regeneration control switch circuit, which is used to command a manual regeneration of the diesel particulate filter (DPF). The PCM expects the switch to pull the signal line low when pressed, but a high-voltage condition tells the module the circuit is open, shorted to power, or the switch contacts have failed.

DTC codes / P25xx · Vehicle speed, idle control and auxiliary inputs / P25BC

P25BCRegeneration Control Switch Circuit High

P25BC indicates that the powertrain control module (PCM) has detected an abnormally high voltage on the regeneration control switch circuit, which is used to command a manual regeneration of the diesel particulate filter (DPF). The PCM expects the switch to pull the signal line low when pressed, but a high-voltage condition tells the module the circuit is open, shorted to power, or the switch contacts have failed.

SystemPowertrain

Code typeGeneric (all makes)

SeverityMedium

Fix difficultyIntermediate

AreaVehicle speed, idle control and auxiliary inputs

Guidance is general and written for all OBD-II vehicles. Exact tests and values vary by model, so confirm the fault before replacing parts.