I replaced my bad cooling fan resister and at first install the cooling fan turned on. Today was a 90 degree day and my temp gauge is red lighted and no cooling fan just power steering fan. Also my A/C will come on then go off then come off. My mini is a 03 hatchback.

 

Is your 2003 a two-plug or one-plug fan? Did you replace the resister with the Dorman thick wire resister or another big green one? Or did you jump the green one with an external resister? Did you take the fan assembly out to do whatever you did?

///Rich

 

Out with the volt meter and check, check, check. +1 on examining the switch too.

 

Its a 2 plug one plug has the heavy gauge wires and the other has 2 thin wires. It was similer to the dorman. Three heavy wires. 2 reds and 1 blue green. I didnt use the blue green one. My original one only used two heavy red ones. The smaller gauge wires went to a relay. I have voltage to the plug with three heavy gauge wires. When I first installed the resister the fan came on like it should, but now that I have driven the car for a couple of days its not coming on. I may have gotten a bad part.

 

Explain step by step exactly what you did. If the resistor goes bad, only the low speed is disabled. The fan should still operate at high speed (triggered by the thermostat). If the fan doesn't come on at all, it might be a bad relay, thermostat, or fan itself.

 

+1 on rechecking everything ... Specifically the wiring...I am guessing it got loose. Did you solder the wires? Use heat shrink tubing? AC won't blow so cold if there is no cooling fan...it triggers the high speed fan to chill the condenser. Not sure what on and off means. Too late here but I am confused as to why people bother with the resistor mod given an aftermarket TYC (with lifetime warranty) is like $65... I am pretty sure that power steering fan is on the same circuit as radiator in your car (my 2003 is).

Also NEVER let the temp gauge hit red...shut the car down immediately.

 

I pulled the fan off. Found the resister to be bad. Installed a new resister using only the the two red wires. I soldered the wires using heat shrink tubing on one wire the other I had to tape since it was to short for shrink tubing. Put it all back together. Everything seem to be working as it should. At least thats what I thought. Is normal operation low speed when the A/C is on and high speed when its hot? Then yesterday. On the way home from work my A/C would blow cold then hot = on /off. The gage was red lighted. No fan was on at all. Only power steering fan was running. The car acted this way with the bad resister also. Whats a aftermarket TYC kit?

 

Maybe the resistor was not the original problem.

 

TYC makes a replacement fan. High speed should kick on at 234, bad resistor or no.
Not sure how hot it has to be for the red light, but that's too hot.

Per the Bentley manual, and confirmed by my ScanGauge, the fan operates at low speed at 221F, and turns off at 214F. The fan switches to high speed at 234F and remains on high until the coolant temps drops by 7F. Supposedly it also turns on when the AC is on and the AC system pressure reaches 8 bar (114psi)

 

Those are some high temps. What does the relay control that is with the resister?

 

THe two stage temp switch controls two relays, fast and slow fan speed. The slow speed remains pulled in (feeding the motor through the resistor) after the fast speed relay pulls in - feeding the fan direct. The power takes the path of least resistance so the fact both relays are energised is not a problem. Same system as the E23 and E32.

 

My scan gauge sees the same...off by 1 or 2 degrees but pretty much the same

 

Those are some pretty high temps. I better look in to my A/C maybe its not getting to 8 bar.

 

+1. The high and low speeds on the relay both connect directly to the fan. The low speed just has a resistor in the path.

Under the conditions you described in the first post, I would have expected the high speed to kick in. I think the relay or thermostat is a possible cause.

 

We'll I found after doing some test. That the thermo fuse on the resister that I just bought burnt out.