3800 Radiator Fan Not Turning On

[J.E.T.]

Problem: Radiator passenger side fan NEVER turns ON.

- Checked fuses - ok (I will check again)
- Checked relays - not much to check here unless I rip them off and test the coils. If the relays didnt work, wouldnt it give me a code?
- Checked wiring of radiator fans - uunpluged connectors and cleaned contacts with electrical cleaning spray.
- Thermo is 160deg. It should be OK.
- Charles checked PCM fan turn on programming - all ok there.

Driver side fan turns on (low speed it seems?) all the time, but the passenger side never, ever turns on. At any outside temperature (even 97 deg like a few weeks ago), my engine temps hardly get past the second big tick mark on the 160deg area. So no worries about overheating even if the fan doesnt turn on.

HOWEVER, who the hell wants to drive around in 97deg temps without AC? Some do, not me! As soon as I turn the AC ON, temps rise past the 210deg mark. The passenger side fan is still NOT on. The driver side fan seems to be on low speed.

Oh well, replace the radiator fan - right? Motor must be burnt or something...
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Not yet.
I just rcvd the Caspers Hi Speed Fan kit. Wow, nice wiring harness. Great quality.
I installed it - doesnt get any easier than plugging in two connectors!! BOTH fans work OK at high speed.

So what the heck is the problem??
I can't figure this out and would like any input.

Thanks,
J.E.T.

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[superchargedgp]

there is a high and low speed relay. replace the high speed one and your fans will turn on

 

[J.E.T.]

Cool! I will try that. I'll have to find one though.

Thanks.

J.E.T.

 

[J.E.T.]

I got some relays in. Troubleshot and swapped relays around (FAN1, FAN2, and FAN something-which is a different relay) . Same result. That passenger side isnt kicking on.

On the bright side, I mounted a different switch for the Caspers Fan Mod and thats working great. I can run the AC full blast and my temps barely climp up.

I'd still like the fans to work the way they are suppose to though.

This is the only thing not working on my car and it bugs me.

J.E.T.

 

[jk99gtp]

JET,

Perhaps the coolant temp sensor has gone bad?

Here is a website on how to test your old relays:

http://users.adelphia.net/~bpaskevich/index_files/Relays.htm

Also make sure to check any ground wires (I think they are by the tranny)...

If you need any help let me know, I'm off work till Sunday. I'll bring my Snap On tool to test anything if needed...

Later...