Overheating and check engine light on 2012 Mercedes GLE Class Diesel: Possible defective coolant thermostat?

Hey, clear case! I had a similar problem with my 2015 Mercedes GLK Classe Diesel. For me, the problem was damage to the wiring harness. I had constant warning lights, similar to yours. The mechanic checked the wiring harness and told me about cracks and chafed areas. Absolutely serious problem. Without a good wiring harness, pretty much nothing will work. Well, they replaced my wiring harness last time and everything has been running like clockwork ever since. Hey, take your car to a garage, especially since you already have so many kilometers on it. Maybe it's the same thing. Good luck, buddy!

(Translated from German)

Hey, thanks for the answer! I hadn't thought that it might have something to do with the wiring harness. Do you remember roughly how much it cost you? And has anything unforeseen happened since then? Hope I don't have any more on my hands... Thanks again!

(Translated from German)

Hey, no problem, you're welcome! So, the damage to the wiring harness cost me around €170.00. But since the visit to the mechanic and the repair, everything is back to normal and the coolant thermostat is working perfectly again. Nothing unforeseen has happened, everything runs like clockwork and it no longer overheats. Hope that helps you. Keep your fingers crossed that everything runs smoothly for you too!

(Translated from German)

You are a lifesaver! 170.00 may not sound cheap, but it's better than a broken car. I'm glad that nothing unforeseen happened after your repair, that gives me hope. I'll take my Mercedes to the garage first thing tomorrow and get it checked out. Thanks again, buddy! You've really helped me out. Keep your fingers crossed for me!

(Translated from German)