P0420 CHRYSLER -

Question

The MIL Light has been on for a while. What procedures should I take so I can verify the actual problem and avoid any unnecessary spending.?

Answer 1

Usually for the P0420 code the problem is the catalytic converter and the best way to verified the catalytic convert is the actual problem is with a gas analyzer. Since the Oxygen (O2) sensor function like a gas analyzer, you can also read how the rear sensor is working, but you need an scanner that can read live data.