fan relay help please fast
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Joined: Jun 2010
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From: Florida
Car: 89 chevy camaro rs
Engine: 305
Transmission: 700r4
fan relay help please fast
first off my fan is wired stright from battary to toggle,and im trying to install this relay can someone give me a write uo of how i would wire this
Joined: Dec 2004
Posts: 2,042
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From: Lincolnton, NC
Car: 88 IROC
Engine: 97 5.7 Vortec LT4 hotcam
Transmission: 700 r4
Axle/Gears: 3.73
Re: fan relay help please fast
Well, this is how I would do it.
Now, find a place to put the relay. I have mine on the radiator support in front of the battery.
1) Find a good place for a ground wire. There should be a spot nearby already where the headlights are grounded. Run a wire from the ground on the relay (85) to the ground on the chassis.
2) Assuming your toggle switch is mounted in the interior, Run a wire from one side of the switch to a keyed power source. In other words, look around the fuse box for an open spot that only has power when the ignition is in the "On" position.
3) The other prong on the switch will go to the Relay trigger pole (86).
4) With a larger gauge wire, with a fused disconnect installed, connect the relay Battery pole (30) to the battery. A junction block located near the battery works great for this.
5) Run a larger gauge wire from the relay pole (87) to the fan positive.
6) Make sure the fan is connected to a good ground. You can probably use the same ground that you used for the relay.
Hope this helps some.
Now, find a place to put the relay. I have mine on the radiator support in front of the battery.
1) Find a good place for a ground wire. There should be a spot nearby already where the headlights are grounded. Run a wire from the ground on the relay (85) to the ground on the chassis.
2) Assuming your toggle switch is mounted in the interior, Run a wire from one side of the switch to a keyed power source. In other words, look around the fuse box for an open spot that only has power when the ignition is in the "On" position.
3) The other prong on the switch will go to the Relay trigger pole (86).
4) With a larger gauge wire, with a fused disconnect installed, connect the relay Battery pole (30) to the battery. A junction block located near the battery works great for this.
5) Run a larger gauge wire from the relay pole (87) to the fan positive.
6) Make sure the fan is connected to a good ground. You can probably use the same ground that you used for the relay.
Hope this helps some.
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Joined: Sep 2002
Posts: 9,192
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From: Cary, North Carolina
Car: 1992 RS
Engine: Carbed 350
Transmission: 700R4
Axle/Gears: 3.42 posi
Re: fan relay help please fast
The relay will not automatically run the fan on/off for you - you'll still have to use the switch to turn it on/off. OR - you can wire the relay so that the fan runs all the time as long as the key is on.
Relay has 5 terminals, marked 85, 86, 87, 87a, 30. Here's the wiring:
85 = 12v+ either from your switch, or from a hot-in-run connection (makes fan run as long as car is on). This can be any samller (18 guage wire)
86 = ground - this can be smaller 18 guage wire
87 = power OUT to fan - this needs to be heavy (10 guage) wire
87a = not used
30 = direct battery power - this needs to be 10 guage wire
What happens:
You turn on key (or turn on switch), 12v+ is sent to 85, and 86 already has a ground, thus activating the relay. The relay, when activated, throws a switch inside, switching the battery power (30 from terminal 87a (not used) to 87 (fan).
Relay has 5 terminals, marked 85, 86, 87, 87a, 30. Here's the wiring:
85 = 12v+ either from your switch, or from a hot-in-run connection (makes fan run as long as car is on). This can be any samller (18 guage wire)
86 = ground - this can be smaller 18 guage wire
87 = power OUT to fan - this needs to be heavy (10 guage) wire
87a = not used
30 = direct battery power - this needs to be 10 guage wire
What happens:
You turn on key (or turn on switch), 12v+ is sent to 85, and 86 already has a ground, thus activating the relay. The relay, when activated, throws a switch inside, switching the battery power (30 from terminal 87a (not used) to 87 (fan).
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