engine cooling fan circuit mod for GA 96-98
3100
07-10-2010, 05:53 PM
Hello people, this is what I did on my GA 97 3.1 because I believe that GAs in general have horrible cooling due to their front grill and bumper design. So if drive your GA mostly in city traffic especially during hot summer days you can do this easy mod as I did on mine. This mod will turn your cooling fan on every time you press brake and turn fan off when brake pedal is released. This modification will not interfere with pcm's fan command. Brake switch is right above your brake pedal and it has orange and Lt blue wires just as on diagram, also cooling fan has lt blue and black wires just as shown on my diagram if you connect everything right you should not have any problems.
So far mine is working good.
orange wire for brake switch is hot at all times, when brake pedal is depressed 12v is sent to Lt blue wire which will send 12V to terminal 86 of relay (86 and 85) is a coil (85) is connected to ground so when 86 receives 12V circuit is closed for 86 and 85 which will create magnetic field and close the switch for terminals 30 and 87. 30 is hot at all times so 87 will get 12v and send it straight to lt blue wire, and black wire is already grounded so this will automatically energize the cooling fan.
I ALSO HAVE DIAGRAM FOR 99GA BUT DID NOT TEST IT, IF SOMEONE IS INTERESTED I CAN SEND IT
again: this will not interfere with pcm's command to turn cooling fan on. Pcm will still be able to turn fan on when necessary and in that case when you press brake lt blue wire will simply receive another positive connection. Just to avoid any confusions: the relay mentioned above and on the diagram is not original cooling fan relay. You have to get your own reley, and also if you want you can install switch so that you can disable this option in winter or during short trips. Switch can be installed somewhere on the lt green wire shown on the diagram.
So far mine is working good.
orange wire for brake switch is hot at all times, when brake pedal is depressed 12v is sent to Lt blue wire which will send 12V to terminal 86 of relay (86 and 85) is a coil (85) is connected to ground so when 86 receives 12V circuit is closed for 86 and 85 which will create magnetic field and close the switch for terminals 30 and 87. 30 is hot at all times so 87 will get 12v and send it straight to lt blue wire, and black wire is already grounded so this will automatically energize the cooling fan.
I ALSO HAVE DIAGRAM FOR 99GA BUT DID NOT TEST IT, IF SOMEONE IS INTERESTED I CAN SEND IT
again: this will not interfere with pcm's command to turn cooling fan on. Pcm will still be able to turn fan on when necessary and in that case when you press brake lt blue wire will simply receive another positive connection. Just to avoid any confusions: the relay mentioned above and on the diagram is not original cooling fan relay. You have to get your own reley, and also if you want you can install switch so that you can disable this option in winter or during short trips. Switch can be installed somewhere on the lt green wire shown on the diagram.
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