I should know this and have searched but want input.

04 MCS goes up to 220 while stuck in traffic. Turning on the AC pulls the temp back down to 195.

Later at home I checked the 50A cooling fuse, it is good.

Running the car in the garage it takes a while but I get to 215 without the fan but turning on the AC starts the fan and pulls the temp down to 191. With the AC on the temp holds at 191.
No low or high speed fan without AC.

Is this just the fan assembly?

After reading the search I am a little confused if it is just the low speed resistor or something else.

Any advice is appreciated.

Thanks

 

The resistor on the fan...the one that allows it to run at a sower speed when needed is burned out.
Simplest fix...install a new fan...for $90... Plus labor...oem os $275-300....so aftermarket fan from rockauto/eBay is a $$$ saver, and they seem pretty good.
More involved fix...repace the resistor...read the thread, order the parts, do the modification, install, test it...and hope the fan motor doesn't fail next!!

 

If you check the threads...turning on the ac causes the high speed to come on to guareentee the airflow to the condensor coil on the ac...the hi speed should come on, no ac, just before the car overheats...the number is published...but I would check it with a scanguage..... If you want to test it, not the dash guage.

 

Thanks for the input.

But I am questioning just the resistor. I know the low speed is not coming on at all. But should the high speed come on before 220?

My SGII showed 220, which is above the posts that say the high speed should come on at 215. I don't want to just run the car until it overheats and does damage to make sure this is the correct fix.
Also, I don't want to replace the fan to find out it is something else.

 

Your thermostat is designed to open at 190 degrees F. The fan should come on as the temperature gets a little hotter (unless the A/C is running). Just not sure how high. I don't recall a low/high speed option. The fan always sounds like it is spinning at the same speed whenever it engages for me.

At least get the issue diagnosed before making repairs. Until then, if you are moving, you should be fine, even on really hot days. If you sit still for a long time, just keep an eye on the temperature and turn the A/C on the lowest setting as needed to engage the fan.

 

high speed fan turns on exactly at 220. should drop your temps back down about 25 degrees or so. i beleive the low speed fan comes on at around 215, but if the car reaches 220, the high speed fan kicks in. you shouldnt have to turn on your ac to get the fan running, so its definitely a fuse or resistor.

 

OK, I am convinced it is the resistor and I need the new fan assembly.
Which one from Rockauto, the $77 or $70 version?
Both seem to be for 2003 forward. One says ($77) 2003-2007 Cooper or CooperS and the other ($70) says 2003-2008, both Cooper or CooperS AND Clubman.
The $70 part seems to cover more range if it is ok.

Thanks