Heck of a first thread here, I apologize.

So my wife's 2009 MCS threw a thermostat code a month ago. Fair enough at ~70k miles.

I ordered a new one and change it out. CEL goes away for a day, then comes back. P0116 and P0597. The latter is t-stat stuck open (it's new, I assume this is bollocks and related to the P0116 based on the following).

I figured out that I derped and crossed-plugs. I socketed the plug that should go in the PCV tube into the temp sensor, and vice/versa. (Nice of MINI to color-code-but-not the plugs there....).

Now however, with everything plugged-in correctly, I still get no signal from the coolant temp sensor (secret menu test #7 yields "+++oC" vs any real numbers.) I figured maybe the new one had fried having been plugged into the wrong thing, so I popped it out and put the one from the old 'stat in to see if that would work. (Prior to replacing, no CEL for temp sensor).

Is there a fuse in-line with the temperature sensor (if so which is it), or if not, have I just gotten a lemon of a replacement t-stat?

(note: I've also fairly thoroughly bled the system).

Many thanks. This has been a fun car, but is quickly running me out of patience. (and I come from working on a stable of mid-engined cars...)

 

Sorry to hear, but i understand the frustration with this cars. Not use to the over engineering of Euro cars, I'm having a heating problem and the system is 100% bleeded.

As to your problem it seems more like maybe your replacement is no good came defective or your fried. The best i can tell you is try to get a replacement from where ever you purchaded it from.

When i get back home ill look and see if there is a fuse for it and where it located.

 

Thanks! That would at least give me a direction in which to go once I'm back in town.

 

I looked, but didn't find anything regarding a Fuse.

 

Check the connection at the wire plug we have seen the tabs break and the plug does not hold on to the top sensor and throws codes.


https://www.northamericanmotoring.co...hermostat.html

 

Thanks for the replies. The problem is resolved.

The wife and I left for a week to attend NSXPO. The MINI sat in the garage, got lonely, then jealous, then thought about what it had done and saw the error in its ways.

By the time we got home, it had repented, accepted Jesus, the temperature sensor was reading actual numbers in degrees, and all of the CEL codes had cleared.

I can only assume it was some stubborn bubble right-at the sensor cavity that survived my repeated bleeding attempts, but over time worked it's way out of the t-stat housing.

 

Thanks for the update, guess it decided to listen.

 

We had a customer who replaced their thermostat themselves and brought it to us due to the exact issue you had, turns out she shorted the temp sensor by plugging it into the PCV heater.

You may be in the clear for now, but there is a chance you will need to replace either the temp sensor, or buy a new thermostat. Good thing MINI parts carry a 2 year unlimited mile warranty through all MINI dealers.

 

That may have been the case with me as well, hence the swap back to the old temp sensor. I didn't feel too bad as one of the more popular walkthroughs on YouTube actually says they are color coded and they go on to mismatch the connections before magically everything works at the end. I will probably go back and tag the wires at some point. Or make some paint pen marks to avoid issues if I do this again.