P04F3

Symptoms

• Check Engine Light Is On
• Increased exhaust toxicity during cold start
• Possible simultaneous presence of code P04F2
• Related Bank 2 Catalyst Error Codes

Causes

• Faulty Bank 2 Catalyst Heater Relay
• Blown heater circuit fuse
• Open or short circuit in the power supply circuit of bank 2 heater
• Bank 2 catalyst heating element malfunction
• General power problem with P04F2 code

How to Fix

1. Read the error codes and check if P04F2 is present at the same time
2. Check bank 2 heater circuit fuse and relay
3. Measure the supply voltage at the heater connector of bank 2
4. Check the resistance of the heating element of bank 2
5. Check the wiring from the relay to the heater
6. If both P04F2 and P04F3 codes are present, check the common power circuit
7. Replace faulty components
8. Reset errors and check the result

Related codes

Error P04F3 by Vehicle Brand