If you find that your car is overheating or running hotter than usual check your fan low circuit is working. To do this start your car and set your heater control to de-mist, start your engine, open the hood and listen for the fan clicking on and off, if it doesn’t you’ve got a problem.
Firstly check the relay for the cooling fan (check with your manual to find the right one, they differ on different models and years) Do this by swapping the relay for one of the others in the box (they are all the same) If still no joy then…..
The fix is to jack up the front of the car on the nearside, then DUCK under the car and find the wires coming from the fan motor and remove some of the protective corrugated cover. You are looking for a yellow and a green wire, cut both of these wires (with the ignition turned OFF of course) strip some of the insulation back, then join the green to the yellow and the yellow to the green. Now cover the twisted wires with insulation tape…and your done! Your fan will now go straight to the high circuit when triggered.
Note; If your low circuit is not working your high circuit will not come on either. The “correct" fix for this is a new ECU!!! (the circuits are switched inside the ECU)
Here is the wire you are looking for, the plug is where the car loom plugs into the fan
Pull the black protective cover to expose the three wires
Cut the green and yellow wires (black is the earth) strip back some insulation and join the green to the yellow and the yellow to the green
Don't forget the insulation tape!
(A neater way would be to use a connector or terminal block to make the connections)