P04F7
Catalyst Heater Circuit High Bank 2
Generic OBD-II
Common symptoms
What you'll notice
- Check the wiring and connectors for any damage or loose connections.
- Inspect the catalytic converter for any signs of damage or clogging.
- Test the oxygen sensors for proper functioning and replace if necessary.
- Check the engine control module (ECM) for any faults and reset if needed.
- Verify the fuel mixture and adjust if it is running too lean or rich.
Common causes
Most likely first
- Faulty oxygen sensor
- Malfunctioning catalytic converter
- Loose or damaged wiring in the catalyst heater circuit
- Faulty powertrain control module (PCM)
- Exhaust system leak
How to diagnose & fix
Work through it in order
- Malfunction indicator lamp (MIL) illumination
- Decreased engine performance
- Poor fuel efficiency
- Rough idle or engine misfires
- Engine overheating
Read & clear P04F7 yourself
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