theedge

Thats what I was going to suggest as well, a pair of switches wired in to give you high low.

Yes, just T it in and have ground on the other terminal of your new switch. If you T it in like that the stock switch can still control the fans when your added switch is off.

theedge

And the best way to T it in is just use some wire strippers to slide the insulation on the wire back a bit in either direction, leaving you a gap of the bare copper wire. Then take your new stripped wire, wrap its end around the exposed section. Solder if youre going to solder, then tape it securely. You dont have to cut the original wire to splice another onto it.

shiners780

So two switches, one tapped into the brown/yellow coolant temp switch wire, the other tapped into the red/white wire.

Is there an easy/convenient source for a 12 volt power supply at the fuse box? So each new toggle switch would have 3 wires, one to one of the wires listed above, one to the 12 v power supply, and a ground? Using this set-up, would I need an in-line fuse for the new switches, or will the stock fan relay take care of that?

In dealing with wiring, I have learned my lesson to ask before doing.

theedge

You want ground, that was my bad I was looking at the wrong switch So ground can go anywhere.

shiners780

What exactly needs to connect to the switches?

1. A wire leading to the brown/yellow (or red/white depending on which switch).

2. A ground.

3. Is there a #3? Don't I need a 12 V power supply?

Pretend you're talking to someone who knows nothing about wiring...because, well, basically you are. Type slowly so I can understand!

xsboost90

i searched but couldnt find it- so what is the advantage of not having the fan running while your on the track? I would imagine it wouldnt turn on while driving unless your getting hot for some reason like hot oil problems or something...

theedge

Nope, thats all you need. You dont need 12 volts. Basically one side of the relay coil is connected to 12 volts, and the thermoswitch just connects it to ground to complete the circuit. Now when shopping for switches, all you need is "Single Pole Single Throw" aka SPST. You can get other styles (SPDT, DPDT, DPST, etc) if you need to, I can help you with wiring other types up.

Now with a SPST switch, its going to have two terminals on it, one terminal can go to ground (id go to the ground point near the fusebox, just for consistancy but thats just me, as long as its to bare metal or a bolt itll work). To the other terminal just run a wire to splice into the wire under the fusebox going to the fan relay. It doesnt need to be a thick wire, 16 or 18AWG is more than enough. Do this twice, one for each of the two wires under the fusebox (hi/low) and youre set.

Like I said, all this is going to do is turn the fans on when you want to turn them on, when the switch is in the "off" position the fans are still controlled by the thermoswitch and will turn on and off like stock. If you want the option to disable the fans entirely regardless of the temp thats doable as well. Also keep in mind that theres not going to be any lights or anything on the switches with this setup, so if you leave the switches turned on when the car is off and dont notice, the fans will happily run the battery down. Adding in lights and completely disabling the stock thermoswitch will change the type of switch you need, so if you want those abilities let me know and I can guide you through it.

shiners780

Perfect information, thank you!

Hopefully, my last question...The switches I have seen have amp ratings. Is there a particular amp rating I must use?

theedge

If youre using the original relay, then any switch will do. Relay coils take very little power.

schwank

I'm going to try this same procedure tomorrow and need to go grab some parts...

can anyone tell me if the second fan still runs after removing the A/C? IIRC from my previous reading it only comes on with the AC fan... is that indeed true?

I had planned to just hardwire the second so it comes on when I hit the switch because I thought the second was only AC controlled. If it still comes on via the fan relay when the engine is warm then I don't really need to do anything.

How about it Jim did you do yours yet?

shiners780

I removed all my AC components, including all the wiring and the relay.

When the car got up to temp, both fans kicked on. This was before I did the wiring procedure as described above (I actually haven't gotten around to it yet).

marky522

Actually the fans purpose is to keep airflow across the radiator to cool the engine at low speeds, the thermostat keeps the coolant in the engine long enough to absorb the heat, then in the radiator long enough to be cooled by the airflow passing through it.

Mark

shazam01

Re 'Hi Speed' vs 'low speed' fans. Please clarify. Is one the 'hi' & the other the 'low"....or is one on the 'low' & both on the 'hi'?
My passenger side motor is not working & I'm looking for a replacement. And, the only way to make the driver's side motor to come on is to turn on the A/C.
Any idea what's going on here?
Shazam

ParkingLotPorsch

Hello, I would really benefit from these direction for replacing the fan circuit. I purchased my car with only one running fan and found the cooling fan relay partially melted with the fuse box. The wire going to terminal 86 is completely corroded and melted and would still not function correctly with a new relay installed. Any help is appreciated, I am going to try and use jumpers to get power to the fans for now.

tempest411

Replace the burned out section of wire as necessary. Loop check all the wiring to insure you have continuity where you're supposed to, and no shorts. It would take some digging, but some here may have a part number for the fuse box terminals if needed. Or, you can cannibalize another fuse box from another car for the parts.