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Yellow Check Engine Light After Thermostat Replacement
Stock Problems/IssuesDiscussions related to warranty related issues and repairs, or other problems with the OEM parts and software for MINI Clubman (R55), Cooper and Cooper S(R56), and Cabrio (R57).
Yellow Check Engine Light After Thermostat Replacement
Yesterday, I replaced the thermostat housing on my 6-speed manual 2013 Countryman S, with an OE housing from Pelican. I also used the the type B harness adapter (based on the last 7 of my VIN) which I got from Herb Chambers Mini. After the replacement, I let the car run in the driveway for about 10 minutes, then drove it for about a mile, then drove it through a car wash (mostly for the undercarriage clean), and finally, drove it back home. There were no leaks, no dash lights, no worries. I posted about the replacement, at the end of this thread.
Then, this morning as my wife was driving the car to work, less than a quarter mile into her trip, she noticed a solid yellow check engine light on the speedo. I don't have an OBD scanner, but the Mini manual says, Engine malfunction with adverse effects on exhaust emissions. She's going to stop by a local shop on her way home to see if they'll quickly tell her which specific code is being thrown. If she gets the code, I'll post it later today.
Here are some details about the housing replacement:
The light definitely never came on yesterday when I test drove the car after replacement, so a crossed wire or hose seems improbable.
Aside from that, I am practically certain that no hoses or electrical connectors were crossed in the process. I don't know about other harness adapters, but the type-B makes it impossible to mix up the wires for the sensors in the housing, and all other electrical connections were either marked by me, or connected to other hardware (tubes, etc) that made it highly improbable to mix them up.
I did not check the coolant level before my wife left this morning, but last night, the coolant level was full and the car hadn't been run between last night when I checked and this morning when my wife left. I can't imagine that enough coolant would be lost in the first quarter mile of her trip to throw a code; but not enough was lost on the remainder of her 5 mile trip to cause the car to overheat or lose performance.
Since (according to the manual) the error seems to be with something that would impact exhaust, might I have not fully connected one of the wiring clips or tubes that connect to the intake pipe (between air-box and turbo)? What about the vacuum lines that I disconnected/reconnected during the install?
Should I plug the temp sensor wire back into the original sensor on the elbow feeding the housing?
If one of the housing wires came loose, what code and dash light should I expect to see?
Can I clear the code without an OBD tool?
I'll check connections, vacuum lines, etc. after work today and post any updates.
Any assistance or practical advice that you experienced Mini mechanics can provide this noob Mini mechanic would be immensely appreciated. I really need the car this weekend for a family trip, and I don't want to run it with a problem.
Having read some other threads, I see that once I have checked connections, hoses, etc., the answer is yes. I can cycle the ignition 5 times or disconnect the battery.
I should also note that I opened the bleed screw on the new housing after I slowly filled the coolant (yesterday). I immediately got coolant coming from the screw so I closed it after no more than a second.
Ah Ha! Found the problem. The first thing I did was cycle the ignition 5 times to verify that that the problem still existed (even though I was confident that it did).
Then I started checking the connections that I could see, without pulling the intake boot, and sure enough this little connector wasn't seated all the way:
To properly seat it, I had to remove the vent tube and then remove the connector from the vent-tube clip and gently wiggle it into place; then hold the clip open (around the connector) as I reinserted the vent tube, ensuring that the ridge on the connector clip seated in the kerf on the connector, and that the seal on the male connector end was fully inserted into the female end.
Then I cycled the ignition again and on 5th cycle the check engine light disappeared. I love it when it's easy!
Last edited by datanerd; Aug 9, 2018 at 02:37 PM.
Reason: typos--I really should have taken a typing class when I was young
Also--I never did get the code since all of the shop techs had gone home by the time my wife got there at about 4:45. Even though the issue is fixed, I wish I knew what the code was.
I'd buy this ECS scan tool today if I wouldn't have to update it from a windows VM on my Mac.