What does code P258C mean?

Q: What does code P258C mean?

Vacuum Pump Control Circuit A Low. P258C indicates that the powertrain control module has detected a low-voltage condition on the control circuit for the vacuum pump, which is typically used to supply brake boost or to operate emissions-related vacuum actuators. The computer monitors the circuit for expected voltage and sets this code when the signal stays below the calibrated threshold for a set time, pointing to a short to ground, an open circuit, or a faulty pump.

DTC codes / P25xx · Vehicle speed, idle control and auxiliary inputs / P258C

P258CVacuum Pump Control Circuit A Low

P258C indicates that the powertrain control module has detected a low-voltage condition on the control circuit for the vacuum pump, which is typically used to supply brake boost or to operate emissions-related vacuum actuators. The computer monitors the circuit for expected voltage and sets this code when the signal stays below the calibrated threshold for a set time, pointing to a short to ground, an open circuit, or a faulty pump.

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.