My low speed on my radiator cooling fans won't turn on. I have the fan switch mod and its worked fine for the last 3 years. Now when I flip the switch for the low speed I just hear the relay click and thats it. But when I flip both the low and high speed switch the fans kick on high, which its supposed to do. I also noticed that while driving the low speed won't kick in either. I swapped the two bottom fan relays which are identical and it made no difference. Weird thing is when I unplugged one of the plugs on the fan and probed it for juice the low fans kicked in. So I then flipped the low switch on and off a few times and the low speed worked but then stopped working again. Any help would be great , Thanks..!

 

Ok I'm wrong the fans should be kicking in on medium setting with the fan mod. So I'm not getting the medium speed. Maybe my #4 relay is bad I didn't swap that one.

 

This is funny I'm posting on my own Thread! Well I've determined that since I swapped the two lower relays (4 and 1) with each other and it made no difference I'm guessing the relays are the NOT the problem. I determined this from the info I found below. That is if the info is correct. Any Ideas?

4 1
3 2
(As viewed from the passengers side fender)


relays 2+4=low fan speed
2+3+4=medium fan speed
1+2+3+4=high fan speed

I've also considered just bypassing the stock relays and wiring and rewiring the stock fans to run with a seperate switch (possibly for high and low setting). I don't drive my FD everyday so it wouldn't be a big deal to watch the temp gauge and flip a switch when needed. Hell I'm already accustomed to watching gauges anyway. I wonder if it would harm anything if I bypassed the stock relays and wiring?

 

The identification of the relays by their location is basically shooting in the dark. It's very easy for someone (you or someone who's worked on the car) to swap the positions on the relay bracket when replacing them for whatever reason. I'd suggest replacing all the relays just to be sure.

Without relays, the sudden amperage draw from the fans will cause an arc that will eventually weld your switch shut.

 

Probably A Relay....imho. But You Really Dont Need Any Other Setting Besides High Anyway!

 

If I can't locate the problem short of replacing all the relays then I'm just gonna bypass the stock relays and harness and rewire the stock fans to seperate switches. I've seen wiring kits that include rellays. By doing this will it change the driving habits of the car? Question is will it harm any thing? Will it alter any settings on my PFC?