Had some work done by a shop when I was up in Minnesota not long ago when the head gasket decided to go. Before the work was done the thermostat and TPMS both worked. I noticed the TPMS light and checked tire pressure before I left for Texas the following morning, and the pressure was fine on all four, just figured one of the batteries in one of the transmitter died, so I headed south. I was about half way home when I also noticed my car had not come up to temp, even after 500+ miles of 80+ mph.

I replaced the coolant temp sensor after I got home, but no change, car stays around 150-170F unless I'm idling a LOT then it'll barely inch past 190F. Thermostat seems to be stuck in full open mode. I went to a tire shop and had them scan the transmitters in the tires, and they said all four were transmitting fine, tire pressure is good too (dash computer states TMPS is "Inactive").

I cant imagine both the thermostat and TPMS failing at the same time, and right after major engine work is just coincidence, but I cant imagine what the shop couldve done to cause these problems, other than something happening to the ECU when they disconnected/reconnected the battery (possibly multiple times). Since the TMPS transmitters are actually working, but the cars computer doesnt think it is, I'm wondering if the thermostat still functions too. Everything else electrical is working properly.

Would a reset of the ECU possibly fix it? Can a normal shop do it, or is this a dealership sort of thing? I can handle working on cars, but the computer/electric side of things is out of my league, so any help is appreciated.

Thanks,
Nick

 

Thermostat on the R56 breaks commonly, getting a new one should fix the issue. Not sure about the tpms though. Oh, maybe you need to initialize them. You have to push the button on the end of the turn signal stalk and then hold it to reset, then drive around a bit

 

I tried resetting/initializing the TMPS, but the computer says its Inactive and the button has no effect.

I just find it too coincidental that both the thermostat and the TPMS both failed after the repairs. They have nothing in common other than being controlled by the computer, but I'm not sure what to do about that.

 

Was it a MINI dealership you brought it too? If it was.. maybe they updated your computer or reflashed it.and of course something didn't initialize correctly..my 2 cents...

 

No, it was a Euro specialty shop, I just emailed them though, hopefully they can think of something. I checked the TPMS fuse and its fine, reset the ECU via the 'hidden' settings on the tachometer screen, no go.

I still need to bring the Mini in to get the timing chain recall fixed, so if I cant figure out whats wrong before then I'll just have them check while they're working on it.