What are the common causes of P04F6?

A short to power in the bank 1 catalyst heater circuit. A failed bank 1 catalyst heater. A chafed bank 1 catalyst heater wire. A faulty ECM heater driver.

Check the bank 1 catalyst heater circuit for a short to power. Measure the bank 1 catalyst heater resistance. Inspect the bank 1 heater wiring for chafing. Replace the bank 1 catalyst if the heater circuit is shorted to power. Clear the code and retest.

P04F6

Catalyst Heater Circuit High Bank 1

System: Auxiliary emission controls (P code)
Lamp: Check Engine Light
Category: Powertrain - Auxiliary Emissions Controls

What it means

P04F6 means Catalyst Heater Circuit High Bank 1.

Check these first

A short to power in the bank 1 catalyst heater circuit
A failed bank 1 catalyst heater
A chafed bank 1 catalyst heater wire
A faulty ECM heater driver

What to do next

Check the bank 1 catalyst heater circuit for a short to power
Measure the bank 1 catalyst heater resistance
Inspect the bank 1 heater wiring for chafing
Replace the bank 1 catalyst if the heater circuit is shorted to power
Clear the code and retest

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Updated

Generic SAE J2012 definition. Last updated 2026-10-10.