On this site: http://www.ls1truck.com/main.html (yeah I am a member there too). Apparently the trucks have the same PCM as the F-bodies so the pin is already there for the fans! There is also a schematic.

This rules for the electric fan crowd. No more relay kits to buy. Just a few $2 relays and some wiring and you are good to go.

BUT...you must have LS1 edit inorder to get this to work. The truck PCM is set up for use without fans so you must adjust the cooling parameters for the fans to kick on.

 

I think when Allen swapped the LS1 into his truck he also used the LS1 computer. The code is in the LS1 computer for the fans but, it may/may not be in the truck computers. I don't know for sure but, have heard that it probably isn't. In LS1edit the option to turn the fans on is there but, from what I can gather that is a generic option that is in every version of EDIT no matter if the computer actually has the code or not. The best way to test this would be to set the fan option on and set a temp. Then probe the pin terminal on the computer to see if it grounds out when the temp hits the set point.

I was kinda concerned about using electric fans because in the past the controllers were not very good but, the controller that comes with the Flexalite 282's is awesome. It has all the features that a stock computer would for the fans and a few more. Once you find the correct wires to tap it is extremely easy to wire up. I think you can buy it seperately and use it for other fans besides the 282's also. The other thing that makes it nice is that you don't have to have EDIT to use it.

I wonder if Allen could shed some light on this.

John

 

He said the LS1 computers and the Truck ones are the same. It states that it is a pin for the fans not just a code.

The Flex-A-Lite VSC is killer. I ordered mine for my F-150 from truckperformance.com about 3 days ago. It is very nice. 60% soft start. Manual On and Off.

I'd just rather have it totally automated via the PCM.

 

I have not tried it, but it should work. There is a pin in the PCM for the fans. Here is the discussion link and wiring scematics do get the job done.

EDIT: forgot to add link Here ya go: https://ls1tech.com/threads/showflat...rue#Post268296

 

Yes it works fine if you just use the primary fan control pin of the PCM. You do have to go in thru LS1 Edit and choose "aux fan", since the truck software comes set as "no fans".
If you have 2 fans and 2 relays you can just tie the relays together so that when the trip temp is reached, both relays kick on.

When developing this feature, there was a minor software glitch when setting the software to "2 fans". When the secondary fan temp was reached, that relay would just sit there click. That may be worked out at a later date.

I just tied both relays together, so that when the trip temp is reached, both fans come on, and it cools down quick!

 

Either way, when I decide to order Edit I will do this. Totally automatic fans sound great to me. Thanks for those schematics.

 

Well, if John says if works I'll go with that.

I'm going to stick with my VSC though because it works great and is a very clean setup.

Actually, It is just a seperate computer when you think about it. I guess being an aftermarket piece the VSC will never be looked at as totally reliable though like the factory computer.

Parish8 - Just unhook the A/C relay hookup to your fans. The fans should still cool the truck down without it.

John

 

I guess I'm a little late with the answer, lol

Ya , it works, try it and find out. It sure is nice not having to worry about manually turning on the fans.

The only problem, which is no biggy, is when the fans kick on, it pulls a lot of juice from the battery and the gauge drops about one notch, but then comes right back up.

I may have on fan turn on one degree earlier then the other just to solve this, but i'm not worried about it.

fyi, i do have the z28 pcm, but it works on the truck pcm too, like speartech said.


later,

allen