What does code P04F6 mean?

Q: What does code P04F6 mean?

Catalyst Heater Circuit High Bank 1. P04F6 indicates that the powertrain control module has detected an abnormally high voltage on the catalyst heater circuit for bank 1, which usually means the heater element or its wiring is drawing too little current or the circuit is open. The computer monitors the heater control line and flags this code when the voltage stays above the expected threshold for a calibrated time, pointing to a fault in the heater circuit rather than the catalyst itself.

DTC codes / P04xx · Auxiliary emission controls / P04F6

P04F6Catalyst Heater Circuit High Bank 1

P04F6 indicates that the powertrain control module has detected an abnormally high voltage on the catalyst heater circuit for bank 1, which usually means the heater element or its wiring is drawing too little current or the circuit is open. The computer monitors the heater control line and flags this code when the voltage stays above the expected threshold for a calibrated time, pointing to a fault in the heater circuit rather than the catalyst itself.

SystemPowertrain

Code typeGeneric (all makes)

SeverityLow

Fix difficultyIntermediate

AreaAuxiliary emission controls

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