Fan relay question...
Fan relay question... I've been searching fan relay wiring threads all morning and my eyes are burning! I found a ton of threads for wiring single fans with 1 or 2 relays and dual fans with three relays, which seems to be the original way GM set the things up..
I have a dual fan set up, with which I bought a fan relay wiring kit from the same company and it has 2 relays in the harness... I have a speartech modified wiring harness that has low speed/ high speed wires..
Without adding a 3rd relay, what are my options for function and control without possibly throwing any error codes!? Can I have both fans run only on low? both run only on high? If I can have them both run on low w/o overheating, I would prefer, just so the fans arent screaming on high all the time.. Appreciate any help wiring these guys up!! Thanks - Jason.
I have a dual fan set up, with which I bought a fan relay wiring kit from the same company and it has 2 relays in the harness... I have a speartech modified wiring harness that has low speed/ high speed wires..
Without adding a 3rd relay, what are my options for function and control without possibly throwing any error codes!? Can I have both fans run only on low? both run only on high? If I can have them both run on low w/o overheating, I would prefer, just so the fans arent screaming on high all the time.. Appreciate any help wiring these guys up!! Thanks - Jason.
TECH Resident
Joined: May 2004
Posts: 792
Likes: 2
From: SoCal
I can't comment on a dual relay setup, but I wired my fans with the GM 3 relay wiring scheme. It does work great; PCM controlled low speed runs both fans in series (so they run 1/2 speed @ 6V; nice and quiet), and can switch over to high speed and runs both fans in parallel (so they run at full speed; each seeing 12V).
Andys
Andys
UPDATE: Actually, my speartech modified harness has only one green wire labeled "Primary Fan Relay"..
And my fan wire harness with two relays has two "+positive+" trigger wires that says to hook up to keyed 12v power. There is also two "-negatigve-" trigger wires that say when grounded, will activate the relays. I'm assuming I hook the green CPU wire to the two negative triggers.. Would this operate both fans on low speed or high?
And my fan wire harness with two relays has two "+positive+" trigger wires that says to hook up to keyed 12v power. There is also two "-negatigve-" trigger wires that say when grounded, will activate the relays. I'm assuming I hook the green CPU wire to the two negative triggers.. Would this operate both fans on low speed or high?
UPDATE: Actually, my speartech modified harness has only one green wire labeled "Primary Fan Relay"..
And my fan wire harness with two relays has two "+positive+" trigger wires that says to hook up to keyed 12v power. There is also two "-negatigve-" trigger wires that say when grounded, will activate the relays. I'm assuming I hook the green CPU wire to the two negative triggers.. Would this operate both fans on low speed or high?
And my fan wire harness with two relays has two "+positive+" trigger wires that says to hook up to keyed 12v power. There is also two "-negatigve-" trigger wires that say when grounded, will activate the relays. I'm assuming I hook the green CPU wire to the two negative triggers.. Would this operate both fans on low speed or high?
