Opel Karl (2017) Overheating and engine indicator light: Coolant thermostat defective?

Hey, I had a similar problem with my 2014 Opel Meriva. In my case, it was damage to the wiring harness that led to similar symptoms. It caused a complete electrical mess, so even the check engine light was on at times. It was a pretty serious thing, so I took it to the garage straight away. It turned out I was lucky because the problem was caught early enough to prevent major damage. They had to replace the entire wiring harness, which took a while. As far as I can tell, everything is now working properly again. Also, there can be no harm in checking the coolant system. Hope that helps you.

(Translated from German)

Hi, thanks for your contribution. That sounds really bad with the wiring harness... Do you happen to remember what you paid for the repair? And has anything else come up since then? I just want to make sure that I only have to go through all this trouble once if I decide to have it repaired.

(Translated from German)

Hey, sure, no problem. So, I paid 110 euros to have the wiring harness repaired. Since then, everything has been running smoothly again, no more trouble. I'm particularly proud that the malfunction of the coolant thermostat has been rectified, it was a real pain in the neck. I hope you're as lucky as I was and don't have to go to the workshop as often.

(Translated from German)

Wow, that sounds bearable. Thanks for the detailed information, I think I'll make an appointment tomorrow. Sure, 110 euros is a lot of money, but if everything really works again and there are no more faults, it's definitely worth the investment. Now I can be a bit more optimistic about the whole thing. Really great, thanks for the help, man!

(Translated from German)