Cooling Fan issues

[Chris McDade]

My cooling fans stop working the other day and I haven't figured out the problem yet. I have the dual fan setup.
I replaced the high speed fan relay with no luck. I haven't tried the low speed one yet. Do I need to replace this one? I think these fans run on high speed all the time. Fuses are good. I have power going to the relays. Fans are good. I put direct power to them and they came on.

What else should I check?

Thanks

 

[larry33kc]

Here you go

http://www.vortexbuicks-etc.com/

 

[Chris McDade]

I've seen the diagram. Thanks

I still can't figure this thing out. I tried my spare ECM last night with no luck. Could a bad sensor cause this? I have a TT chip so, when I start the car the fans come on. I don't have to wait for the car to get to temp.

Thanks,

 

[mgmshar]

When the chip commands the fans to turn on, the ECU fires the LOW speed relay. Most people have their fans wired so that when the low speed relay comes on, the fans will go to high speed.

Try replacing your low speed relay. For a quick test, swap your high and low speed relays and see what happens.

 

[williamsGN]

Start tracing power down the lines to the fan with a voltmeter. My stocker stopped working when the connector gave out that plugged into it, I ended up hard wiring it together.

 

[Chris McDade]

Swap relays already...no luck. One relay is brand new. So, I know it's good.

 

[huntsg]

Ive had the same issue with my fans. I put my stock fan back in and have had no issues. I'm wondering if it's the wiring harness. Mine is a caspers. Where did u get yours?

 

[salvageV6]

Ground the thinner green trigger wire on the low speed fan relay and see if they come on. Key ON test with relays plugged in use a pin or slide the socket down a bit to get a grounded wire to touch the contact where the green trigger wire is.

 

[Chris McDade]

Salvage,
I did that last night. I grounded the green wire with it plugged into the relay and nothing. I even did it on the high side with the green/yellow wire and still nothing. Ugh!

 

[salvageV6]

Then its the relay or power to feed the relay coil or relay high current power feed to the contact that runs the fans.
Id check the relay fuse first make sure with jey on you have pier on the punk/black stripe wire and on the fat red high current power wire.
You can first test those feeds with the relay unplugged.

 

[salvageV6]

Okay after reviewing the vortex diagram the relay power + 12 is on the brown wire look for + 12 on that with key on.