P04F8

Catalyst Heater Circuit Intermittent Bank 1

Severity

⚠️ Medium

Can you drive?

Limited driving only, diagnose soon

Approx. repair cost

$56–167 (est.)

Symptoms

Check Engine light comes on
Reduced catalytic converter efficiency
Possible increase in fuel consumption
Unstable engine operation at idle

Causes

Damaged catalytic converter heater
Open or short circuit in wiring harness
Faulty heater circuit relay or fuse
Poor contacts in circuit connectors

How to Fix

Check the condition of the heater circuit fuses and relays
Inspect the wiring harness for damage
Check connectors for oxidation and poor contact
Check the resistance of the catalytic converter heater
If necessary, replace the heater or damaged circuit elements

Related codes

P0420 P0430 P04F0