'99_Tahoe LS 4WD - AZ
Member
Thanks for the forward @HiHoeSilver
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Thanks for the forward @HiHoeSilver
To be honest, I would build a three relay setup like the 05 on up trucks came with. But then you would also need two triggers. That way, one trigger can turn one fan on high speed, or the second trigger would turn both fans on at low speed. If both triggers are activated at the same time, then BOTH fans will run at high speed. On the OEM harness, one trigger is the temperature trigger, and that turns both fans on at low speed. The second trigger is connected to the AC compressor, and turns one fan on at high speed if the AC is on. But if the engine is up to temperature, AND the AC is on, then BOTH fans run at high speed.
Don’t stress over it too much.
I’ve been running the original FAL controller on my fans for at least 5 years now. The only problem I had was right after the install. It blew the 30amp supplied fuse. After putting an amp probe on it and seeing that it pulls 36 amps I changed the fuse to a 40 and it’s been fine since.
I did have to replace a motor about 6 months ago.
Don’t stress over it too much.
I’ve been running the original FAL controller on my fans for at least 5 years now. The only problem I had was right after the install. It blew the 30amp supplied fuse. After putting an amp probe on it and seeing that it pulls 36 amps I changed the fuse to a 40 and it’s been fine since.
I did have to replace a motor about 6 months ago.
Thanks very much, Kevin @fire730 , I'll put a 40 amp fuse in there instead of the 30.