So just replaced my 02 r50 with a 2011 Clubman r55 and of course this one has the SAME issue my old one did. Just hit 58k miles on it. My first car had a coolant leak but that was an easy fix. So far I've checked coolant with no leaks but the check engine light popped on and now the fan stays running for about 5-8 minutes after the car is off regardless of how far I travel, even starting it up for a few minutes. So far it hasn't drained the battery. Running the code scanner I got P0117 (Engine coolant temperature low). Anyone else seen this? I've read the thermostat issues but could it be a sensor? Or a problem with the coolant reservoir?

 

This usually points to the coolant temp sensor or a bad thermostat. If you touch rad hose after long drive, it is hot, not warm?

If it is hot, the thermostat is probably OK and the sensor is bad IMO.

 

bump

Having the very same issue. (on N14 R56)

Old thermostat was leaking so i replaced with a new thermostat + sensor. CEL (p0117). Sent the thermostat back and replaced with another...still having same problem.

Live torque data showed normal coolant temp readings (180-220), but it intermittently pings to -40 causing the CEL. I've cleaned the connectors and checked the wiring for any breaks or openings and haven't found any. At a loss for what to do now :(

 

1. Is the car an automatic? If so, clear the codes stored in all modules. The trans controller stores engine faults and will still cause problems if the temp code is stored in the trans controller.

2. Make sure the PCV heater isn't plugged into the thermostat temp sensor, I've seen it multiple times and it causes all sorts of problems, like; hard starts, no starts, rough idle, and I've had to replace a couple thermostats due to them being burnt out.

3. Is the thermostat you're using an OE unit? We were using an aftermarket unit for a very short time in the shop until we started seeing a huge failure rate in them. We only recommend the OE units at this point.

 

All sorted out. Turned out to be a poor connection. Re-cleaned and re-seated all connections, and it's been fine ever since. Not sure if they did an update, but you cannot swap any of those connections on mine. I thought i may have had them backwards, so i tried to swap, and they would not fit in any other port but their own.