PontiacBonnevilleClub.com

This should work:


Most pink wires running to the main fuses at the top of the engine bay are keyed on +12v. I run my electric water pump relay off of one of these wires as per it's install instructions.

Also just to be 100%, the thermostat is the controller and there's a temp probe going from that to the rad, right?

Correct. So one post from the thermostat goes to terminal 85 and then another wire from a 12v switched goes to the other terminal? Terminal 85 is for sure a constant 12v? It doesn't turn on with that wire, but when I had it on the large red wire (terminal 30) it turned on. Also would I have to do anything with any other terminal than the 12v on the relay end?

I think I see the problem, you're showing an aftermarket relay with the same diagram wired into the stock high speed relay, from which one terminal is ground and another 12v for the thermostat, and then a switched 12v to the other terminal on the thermostat. Is that correct? I misunderstood if so, I thought I could use just the stock high speed relay without adding one.

Yeah, I should have been more clear, you need to add another relay for this to work.

So the reasoning for wiring it up this way is:

-You're using the stock, fused, fan power source
-You use the thermostat (switch) to energize the coil in the second (new) relay which trips the relay and delivers power to the fans
-You're using a +12 source for the relay that's only activated at key on
-The fans will operate as stock otherwise

Alright, I'll have to grab a relay at work tomorrow then. My bad for not understanding, though it all makes perfect sense now.

No worries. Let us know how you make out.

I've been told very well. Oh wait. Wrong thing!

Should finish this up in the next couple days.

Loll. Puns are the best.

I've no idea what I keep doing wrong. I wired in the relay exactly as shown, and tried the pink wires, it won't come on while running. When I shut the car off connected to the pink wire it came on after I shut the car off. I switched to a red wire in that same loom and now it won't come on while runnkng still, but nor will it come on when the car is off. I'm stuck.

Have a multimeter?

I would check to make sure pin 30 on the stock relay is +12 all the time, pin 87 on stock relay is grounded, and the pink wire is +12v when keyed on.

Once that's verfied, try wiring it up sans the thermostat and see if the fan comes on with key on.

I don't have a meter here. I'll have to bring it by work sometime.

Not sure what this means, but if I take the wire off the red one in the loom am put it to ground the fans come on. Key on or off. But if I touch it to the positive post of the battery they do not come on.

That would only happen if the new relay you used defaults to closed or if you wired the ground to +12v.

Have a part number or picture of the new relay?

I don't, but it has the same pattern and terminal numbers as the stock one. I believe it's actually an aftermarket horn relay. It's possible that I switched two wires somehow.

FWIW rhw wire I'm referring to is the one from terminal 2 on the thermostat.

This is what I'm working with.

This is strange since it does have the same pin out as stock.

SSEiMan01 wrote:Not sure what this means, but if I take the wire off the red one in the loom am put it to ground the fans come on. Key on or off.

This doesn't make sense because that puts both sides of the new relay's coil circuit at ground and it should not close the relay.

SSEiMan01 wrote:But if I touch it to the positive post of the battery they do not come on.

Do the fans come on if you go straight from the 85 terminal on the new relay to the positive terminal on the battery?
(with 86 grounded as in the diagram)

I'll have to try that in the morning. That relay is definitely default open, we ohmed one out to see.

I'll try that in the morning and see and bring it to work and check things out. My coworkers think maybe the thermostat is bad and grounding terminal 2 completes a circuit and turns the fans on.

Make sure you check this out too:

95naSTA wrote:I would check to make sure pin 30 on the stock relay is +12 all the time, pin 87 on stock relay is grounded, and the pink wire is +12v when keyed on.

Once that's verfied, try wiring it up sans the thermostat and see if the fan comes on with key on.

And here are your instructions in pdf form:
http://www.haydenauto.com/Upload/Hayden ... mostat.pdf