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KevStraw

Persistent Fault with No 3 Heater Plug in Mercedes A-Klasse

Check engine light on

I own a Mercedes A-Klasse and recently, the check engine light came on. I used Carly to diagnose the issue and it indicated that the No 3 heater plug was faulty. I replaced it but after just 2 days, the same fault has reappeared. Has anyone else experienced this issue? Any suggestions on what could be causing this persistent fault and how to fix it?

1 comment(s)


CarlyMechanic

It's possible that the issue isn't with the heater plug itself, but with the wiring or the relay that controls it. I would suggest checking the wiring for any signs of damage or corrosion, and testing the relay to ensure it's functioning correctly. If you're not comfortable doing this yourself, it might be best to have a professional mechanic look at it. Please keep us updated on your progress. Do you have any other questions?

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