Fan Override (Eliminates the CEL/SES problem)
Originally Posted by BillBoost37
Here is the relay pack I made. It'* 6 in total and I've bench tested it. Works good.


I have an electrical background, and .....
wondered.... why six relay'* to turn on a fan?
One by itself should be enough to do the fan and, a light...
battery power thru relay, to fan, controlled by switched coil, with indicator lamp
(an LED) in the coil circuit. ( Or if you want areally BIG bulb, put it in the battery side...)
I'm lost on this exercise. and I'm obviously missing something here.
(sniff)
Thread Starter
Joined: Mar 2005
Posts: 41,391
Likes: 30
From: Enfield, CT






The problem isn't turning the fan on, or turning it off.
The fan mod is done by grounding the same wire as the pcm to the high speed fan relay on the car. Any switch will do and work fine. Some of us forgetful people see our temps lowered and don't turn the switch off. So far no problem, car is turned off and fans turn off. Upon the next restart the fans turn on and the pcm diagnostic sees the fan on. The service engine soon light comes on to tell you there'* a DTC code to help you troubleshoot not turning the switch off to your fan override.
Here'* the part, yes a single relay latching itself from momentary switch would work. I'm into options, I want to be able to turn it off and on from a single switch. And a single relay can not do that.
I wanted a latching on/off system and chose to pick up some relays at the junkyard. (Cost: Free) Hook then together properly according to the latching/unlatching setup. I hook the power to ignition power and it automatically resets when the car is turned off.
Diagrams can be found here. 4th or 5th will do a postive output. Add one relay to output ground.
http://www.the12volt.com/relays/page5.asp
Or it could be done via circuitry using an IC flip flop chip
http://www.imagineeringezine.com/PDF...13oneshots.PDF
I was unable to appropriate a flip flop yet and therefore haven't finished that part of my project.
The fan mod is done by grounding the same wire as the pcm to the high speed fan relay on the car. Any switch will do and work fine. Some of us forgetful people see our temps lowered and don't turn the switch off. So far no problem, car is turned off and fans turn off. Upon the next restart the fans turn on and the pcm diagnostic sees the fan on. The service engine soon light comes on to tell you there'* a DTC code to help you troubleshoot not turning the switch off to your fan override.
Here'* the part, yes a single relay latching itself from momentary switch would work. I'm into options, I want to be able to turn it off and on from a single switch. And a single relay can not do that.
I wanted a latching on/off system and chose to pick up some relays at the junkyard. (Cost: Free) Hook then together properly according to the latching/unlatching setup. I hook the power to ignition power and it automatically resets when the car is turned off.
Diagrams can be found here. 4th or 5th will do a postive output. Add one relay to output ground.
http://www.the12volt.com/relays/page5.asp
Or it could be done via circuitry using an IC flip flop chip
http://www.imagineeringezine.com/PDF...13oneshots.PDF
I was unable to appropriate a flip flop yet and therefore haven't finished that part of my project.
Originally Posted by BillBoost37
The problem isn't turning the fan on, or turning it off.
Here'* the part, .
I'm into options, I want to be able to turn it off and on from a single switch.
it automatically resets when the car is turned off.
Here'* the part, .
I'm into options, I want to be able to turn it off and on from a single switch.
it automatically resets when the car is turned off.
Make up a few and sell 'em as kits!
Everyone asks for aftermarket stuff.....LOL!
Senior Member
True Car Nut
Joined: Sep 2004
Posts: 9,130
Likes: 0
From: Farmington, Minnesota =MWBF '05 SURVIVOR= =CEBF '06 SURVIVOR= =August '06 COTM=

Originally Posted by Charliebonn
Originally Posted by BillBoost37
The problem isn't turning the fan on, or turning it off.
Here'* the part, .
I'm into options, I want to be able to turn it off and on from a single switch.
it automatically resets when the car is turned off.
Here'* the part, .
I'm into options, I want to be able to turn it off and on from a single switch.
it automatically resets when the car is turned off.
Make up a few and sell 'em as kits!
Everyone asks for aftermarket stuff.....LOL!
Boost is getting smart again....interested in what kinda crap he'll come up with next??
LOL
Originally Posted by LakevilleSSEi
I'd buy one......
Boost is getting smart again....interested in what kinda crap he'll come up with next??
LOL
Originally Posted by 1993 SLE
Originally Posted by LakevilleSSEi
I'd buy one......
Boost is getting smart again....interested in what kinda crap he'll come up with next??
LOL
also, I talked to him about selling them. The cost to you before he starts even making money would put the while kit out of most peoples price range. All the info is here, really, you should just make your own.
Originally Posted by corvettecrazy
Originally Posted by 1993 SLE
wait till u see the final install of the button and his Hands free car kit
also, I talked to him about selling them. The cost to you before he starts even making money would put the while kit out of most peoples price range. All the info is here, really, you should just make your own.
WHAT?? for "free used relays" and some "hookup wire"?? and OK.....
a few minutes soldering work?
No, not "Soldiering".... not "soderen" No not Saddam.....
Even if he charged $2000./ hr, that'* only $166.00 for five mins work....
Hey! The shipping costs alone, should come to more than that.....
Thread Starter
Joined: Mar 2005
Posts: 41,391
Likes: 30
From: Enfield, CT






Charlie. Call me slow, I set out on the first one using 1/2 sized relays instead of full. Translating from 85,86,87 back to 1,2.3 was a bit of a pain. I did another with full sized relays. It probably took me close to 45mins to toss it together. Qualtiy work is not quick.
But..with that said. Who wants one? I'll make a few up and sell them reasonably.
But..with that said. Who wants one? I'll make a few up and sell them reasonably.
Originally Posted by BillBoost37
Charlie. Call me slow, I set out on the first one using 1/2 sized relays instead of full. Translating from 85,86,87 back to 1,2.3 was a bit of a pain. I did another with full sized relays. It probably took me close to 45mins to toss it together. Qualtiy work is not quick.
But..with that said. Who wants one? I'll make a few up and sell them reasonably.
But..with that said. Who wants one? I'll make a few up and sell them reasonably.
Aww... come-on!
I was just kidding around, with CC'* post.. is all




