aux fan control

[Maniak]

I'm looking for another way to control my aux trans fan.

I've tried temperature controls, but if the fan is running when the temp is high and I'm moving fast it actually limits the air to the cooler.

I currently have it setup so that when the torque converter is locked the fan is off. When the converter unlocks it uses a capacitor to keep the fan from turning on until 5 seconds later (that way a quick tap of the brakes doesn't turn the fan on right away)..

The idea I had was to maybe connect through the cruise control. The CC won't turn on until about 35-40mph which seems like the right idea. When the CC is allowed to be turned on the fan would not run, but when the CC isn't allowed to run (low speed) the fan would be running.

Does anyone know how the CC works.. Does the EEC put a signal on a wire (12v or ground) that I could tap into to kick a small relay that would then kick the big control relay on the fan?

I can't tell if it does the above or if everything is just internal to the eec to the point where I can't hook into it and know when CC is allowed to be run.

~Mark

 

[pope_face]

I have no idea, but it's an interesting idea...

 

[ExploderHOKIE]

you can always hook it up to a manual switch

 

[pope_face]

Isn't the speedo run off a cable? If it is, maybe it does a similar thing to the TPS where the CC can be activated at a certain voltage... if so, you may be able to hook up something that would only allow the fan to run up to that voltage...

Anyone have any input?

 

[Maniak]

The speedometer is run from a cable, but there is a speed sensing unit on the cable that tells the computer how fast the truck is going.. And based on some internal logic it allows the CC to turn on at 35. What I'm looking for is a way to know when the computer says its ok to run the CC..


BUT, thinking about it some more.. when I'm in 4x4 low mode I may want the aux fan to run all the time anyway.. OD, with the conveter locked in 4x4 low for me is about 45mph tops which means when in 4x4 low we will really never be going fast enough to not need the aux fan.

So, even if I figure how to make it run when the CC is allowed I will need need to add a 2nd trigger so it will run when the truck is in 4x4 low (that should be easy to capture).

~Mark