Condenser/Radiator Fans

[Antigenus]

I just drove 2 hours to buy new fans for my radiator and when I plugged them in, nothing happened. So besides being utterly upset, I kept at it and found the problem. When I test the 4 prong snap cuppling for the electrical feed to the fans, i got 12volts out of the top 2 prong, and nothing from the bottom 2. The problem is, that the bottom two which im guessing are the grounds arent grounded. I looked thru every relay, fuse, etc. Nothing is bad. I ran 2 bare wires from the battery terminal to the male end of the snap fitting attached to the fans and BOOM they worked. My next issue is how am I going to fix this. I dont know if its a bad thermastat, or the ground wires feeding it are junk. I'm so sick of this problem. If i cant figure this out, im about ready to hardwire these fans in, and put a toggle switch in my damn cockpit.

[Earthworm]

The fans don't turn all the time unless the A/C compressor is running. Try that and if it still doesn't work check for engine and climate control error codes.

[ensteele]

Did you try the others to see if they were still good? Let us know what you find out. Thanks.

[Trevor]

EXACTLY when are the fans NOT operating when they SHOULD be?

The fans have only one ground connection within each plug i.e. no. 3, and are multi speed with three positive connections making the four you have found.

Control is via four relays, located in the air conditioning relay holder, in a row along with two fuses, one fuse for each fan. This holder is located under the hood alongside the other fuses etc. The relays are actuated via the A/C and MPFI control units. It will most certainly not be possible to fit a simple switch as you suggest.

Unfortunately the wiring diagram is rather confusing, but it would appear that the motors have more than one field winding in order to achieve multi speeds. Sorting out the actual sequence of operation would require a lot of time, which I do not have at the moment. In particular you should check supply fuses 3, 21 and 25 in the main fuse unit and the two in the relay holder as above.

The water temperature sensor has two connecting conductors, neither to ground. I would expect it be more than a simple on/off thermal switch, but can find no reference to it as being a thermistor or a thermocouple. It is connected via the loom to the MPFI control unit. This is not the only item involved in the control circuit as you must appreciate.

[Antigenus]

I successfully located the right positive prongs for the highest speed. I hardwired a circuit (I pulled wires thru the firewall) from the battery to the fans with a toggle switch next to my power seat button. This allows me to turn it on/off with a simple switch. Its gonna get me once I know when I forget to turn it off or something, but for now, and not bothering with anymore BS electrical this does the trick. The hose on the top of the radiator is rotten. The clamp i have on there is cutting around the clamp and just falling apart, I'm going to replace that today.

[Trevor]

Originally Posted by Antigenus

I successfully located the right positive prongs for the highest speed. I hardwired a circuit (I pulled wires thru the firewall) from the battery to the fans with a toggle switch next to my power seat button. This allows me to turn it on/off with a simple switch. Its gonna get me once I know when I forget to turn it off or something, but for now, and not bothering with anymore BS electrical this does the trick. The hose on the top of the radiator is rotten. The clamp i have on there is cutting around the clamp and just falling apart, I'm going to replace that today.

Sounds like your SVX has had and continues a sad life.