Coolant Temp alarm after carwash

[Bret11]

Originally Posted by crystalworks

Yep, especially if using the undercarriage cleaning versions.

The only other thing I could see it being (without actually looking at the vehicle) is an auxiliary fan issue. If that's not working you might experience overheating under certain circumstances. Like going through a tunnel wash with no air moving over the radiator. Not sure if those places use heated water, but that could also contribute.

^I don't think the above is likely. But if you see the needle do the same thing in the future it's something to take a look at. It's a known failure point on the E53.

Thanks crystalworks. I'll keep the potential auxiliary fan issue in mind.