What does code P2B79 mean?

Q: What does code P2B79 mean?

Coolant Heater B Control Circuit Performance. P2B79 indicates that the powertrain control module has detected a performance fault in the control circuit for coolant heater B, which is typically a supplementary electric heater used to warm the engine coolant or passenger compartment quickly after a cold start. The computer monitors the circuit for expected electrical behavior and sets this code when the heater's response does not match the commanded state within the programmed time or current limits.

DTC codes / P2Bxx · Hybrid propulsion / P2B79

P2B79Coolant Heater B Control Circuit Performance

P2B79 indicates that the powertrain control module has detected a performance fault in the control circuit for coolant heater B, which is typically a supplementary electric heater used to warm the engine coolant or passenger compartment quickly after a cold start. The computer monitors the circuit for expected electrical behavior and sets this code when the heater's response does not match the commanded state within the programmed time or current limits.

SystemPowertrain

Code typeGeneric (all makes)

SeverityLow

Fix difficultyIntermediate

AreaHybrid propulsion

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