Both Fans On
Thread Starter
Instructor
Joined: Jun 2005
Posts: 200
Likes: 0
From: Prince Frederick Maryland
Both Fans On
Hey guys, I know someone on here made a post on how to have both fans come on when the auxillary one does. Over the weekend I changed out the coolant temp sensor for one that comes on at 170 degrees which only turns on the aux fan. Does any one have the post or know what I need to do to get the main fan to come on at the same time? Thanks 
Le Mans Master
Joined: Jun 2006
Posts: 5,642
Likes: 5
From: One day you're a Comet...the next day you're dust... Arkansas
If it's your 1989 the main fan works off the ECM. I guess you could haywire the main fan relay to take it's ground from the sensor you just installed. It is unnecessary IMO. I put a 200* aux fan sensor on my 1989 2 years ago and it works great. Why run both fans all the time? Your car was designed to run at 195* and above. Also wear and tear on fans would be more than necessary.
Last edited by BADDUCK; Apr 3, 2009 at 01:43 PM.
Burning Brakes
Joined: Feb 2009
Posts: 785
Likes: 3
From: Richmond Virginia
If it's your 1989 the main fan works off the ECM. I guess you could haywire the main fan relay to take it's ground from the sensor you just installed. It is unnecessary IMO. I put a 200* aux fan sensor on my 1989 2 years ago and it works great. Why run both fans all the time? Your car was designed to run at 195* and above. Also wear and tear on fans would be more than necessary.
Burning Brakes
Joined: Mar 2008
Posts: 1,030
Likes: 1
From: My Give A Dams Busted The Bend Me Over State N.J
I have both of mine hooked up to one switch. I think I did this when I was drag racing. Its ok if you want to watch the gauge and turn them on and off. I dont mind its part of driving it.
Safety Car
Joined: Oct 2008
Posts: 4,689
Likes: 4
From: Yucaipa CA
find the relays for both fans. take ground wire from you 170 degree sensor and use it to ground the green or blue wire on each relay and both fans will run of the one sensor. I did it like this on my 90
