Have a weird gremlin..

SpicySeth · 12-31-2021, 12:51 AM

I have a 2015 M235i with 39k miles and I've had an issue that I haven't had any luck getting rid of. I'm wondering if anyone else has some input or experience with this.

Code:
1D2008 map-controlled thermostat: stuck open

The radiator fan will blow at high power and extremely loud.
The oil and coolant temps don't get much higher than 160f even after about 20mins driving.

I have had the thermostat and coolant temp sensor replaced with no luck. I can't seem to get rid of this issue, can anyone else share some insight or help?

Thank you.

aerobod · 12-31-2021, 02:31 AM

Has the wiring to the thermostat and temp sensor been checked for damage? A charge pipe change could cause damage to the wiring or connector, if not done carefully, if that has been done on your car in the past.

XutvJet · 12-31-2021, 09:41 AM

Try this

https://www.google.com/url?sa=t&sour...OIOTeQNc7XDl4-

ctt300 · 12-31-2021, 02:52 PM

I had this issue and it still occured after replacing the thermostat. It ended up being that the coolant level was just low enough so I filled it to the max line and all was well. So moral of the story is to check the simple things first.

SpicySeth · 12-31-2021, 05:53 PM

Thanks for the input guys, I'm going to start with the coolant level first. My driveway has pretty steep slope to it so I just pulled the car out and will let it cool a little.

I haven't even looked at the wiring but I'll check that out next.

According the the TSB the only thing left would be the auto trans heat exchanger. I had a shop look at that recently and they said it was functioning properly so if none of the options above help I'll take it somewhere to have it swapped.

SpicySeth · 01-01-2022, 01:35 PM

Update: Coolant level was at max. Not experienced enough with electrical to know where the connections are but I will look there when I have some more free time.

Happy New Year people!

SpicySeth · 01-10-2022, 02:32 PM

Another update:
Took the car to a buddy who's a BMW tech and looks like the trans cooler is working fine too. He found the engine harness is in bad shape and has some Mickey Mouse "repair" to it. I just got the car a couple months ago so possibly a remnant if the previous owners handy work.

F8KM2 · 10-02-2022, 11:10 PM

Were you able to figure out that is was the wiring harness? I've been chasing this problem for years and you have the same year/car as me. Any help would be great!

12-31-2021, 12:51 AM	#1
SpicySeth Registered 0 Rep 4 Posts Drives: M235i Join Date: Dec 2021 Location: CA iTrader: (0)	Have a weird gremlin.. I have a 2015 M235i with 39k miles and I've had an issue that I haven't had any luck getting rid of. I'm wondering if anyone else has some input or experience with this. Code: 1D2008 map-controlled thermostat: stuck open The radiator fan will blow at high power and extremely loud. The oil and coolant temps don't get much higher than 160f even after about 20mins driving. I have had the thermostat and coolant temp sensor replaced with no luck. I can't seem to get rid of this issue, can anyone else share some insight or help? Thank you.
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12-31-2021, 02:31 AM	#2
aerobod Car Geek 3612 Rep 3,578 Posts Drives: Caterham R500, M2-G87, Macan S Join Date: Mar 2008 Location: Calgary iTrader: (0)	Has the wiring to the thermostat and temp sensor been checked for damage? A charge pipe change could cause damage to the wiring or connector, if not done carefully, if that has been done on your car in the past.
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12-31-2021, 09:41 AM	#3
XutvJet Major General 5538 Rep 5,364 Posts Drives: 2011 Cayman Base, 2016 M235 Join Date: Mar 2016 Location: Kansas City iTrader: (-1)	Try this https://www.google.com/url?sa=t&sour...OIOTeQNc7XDl4- Last edited by XutvJet; 12-31-2021 at 09:46 AM..
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12-31-2021, 02:52 PM	#4
ctt300 Private First Class 47 Rep 142 Posts Drives: F30 335i Join Date: Feb 2019 Location: Sunny Florida iTrader: (0)	I had this issue and it still occured after replacing the thermostat. It ended up being that the coolant level was just low enough so I filled it to the max line and all was well. So moral of the story is to check the simple things first.
	Appreciate 0 Quote

12-31-2021, 05:53 PM	#5
SpicySeth Registered 0 Rep 4 Posts Drives: M235i Join Date: Dec 2021 Location: CA iTrader: (0)	Thanks for the input guys, I'm going to start with the coolant level first. My driveway has pretty steep slope to it so I just pulled the car out and will let it cool a little. I haven't even looked at the wiring but I'll check that out next. According the the TSB the only thing left would be the auto trans heat exchanger. I had a shop look at that recently and they said it was functioning properly so if none of the options above help I'll take it somewhere to have it swapped.
	Appreciate 0 Quote

01-01-2022, 01:35 PM	#6
SpicySeth Registered 0 Rep 4 Posts Drives: M235i Join Date: Dec 2021 Location: CA iTrader: (0)	Update: Coolant level was at max. Not experienced enough with electrical to know where the connections are but I will look there when I have some more free time. Happy New Year people!
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01-10-2022, 02:32 PM	#7
SpicySeth Registered 0 Rep 4 Posts Drives: M235i Join Date: Dec 2021 Location: CA iTrader: (0)	Another update: Took the car to a buddy who's a BMW tech and looks like the trans cooler is working fine too. He found the engine harness is in bad shape and has some Mickey Mouse "repair" to it. I just got the car a couple months ago so possibly a remnant if the previous owners handy work.
	Appreciate 0 Quote

10-02-2022, 11:10 PM	#8
F8KM2 Registered 0 Rep 3 Posts Drives: 2015 M235i Join Date: Sep 2021 Location: Portland, Oregon iTrader: (0)	Were you able to figure out that is was the wiring harness? I've been chasing this problem for years and you have the same year/car as me. Any help would be great!
	Appreciate 0 Quote