Well I had some sheetmetal laying around so I thought I would go ahead and build a fan shroud for some Fans. I ordered some Summit 12 and 14 fans cause that was as big as I could go on the fan size and make them fit on a 28" radiator. I did my research and I decided to use pin 33 and 42, but that ran into a few problems I will explain later, OH and I decided to knock the dust off my sheetmetal tools and roll some beads into the sheetmetal, but I did not have anyone to turn the crank so they are not perfectly straight . Anyways here are the pics

Sheet metal pattern



Mockup



Finished w/ homemade relay



Installed

 

So know the problems, well I used EFI Live to program the PCM to turn on the Efans. I set the parameters to Series so both fans will activate. The fans work perfectly if I use the bi-directional controls, but if I let the computer do its thing, they just stay on high? So I am kinda stumped, I have tried about 3 dozen different temp and AC settings and even tried Aux fans instead of series, and I even messed with the AC parameters changing from Auto recirculation to Fan #2 still the PCM has the fans high all the time. The harness is correct cause I can disconnect the lead from the PCM and ground them and they work, and the bidirectional controls work too, so I am stumped.....

 

Looks great

Just a suggestion, but I see youre using the 3 relay set up. Why not use just pin 42, and let the relays control the high/low speeds? Just a thought

 

I figured out the problem. I had the display settings on EFI live setup as kPa instead of PSI, and I was inputing PSI values, so the reason they were always on is because my AC enable setting were set to something like 30 psi. So I changed the display units in EFI Live to PSI and kept my same settings and everything works perfectly. The fans don't come on until they are supposed to!!!! So now the AC pressure is in control and the temp is also in control. Oh and my AC is really cold and it is ~97* outside right now.

Here are my settings.


The reason I am using both pins is because I read alot of threads about the efans cycling too much and this was one of the solutions I found to correct it.

 

very, very nice. you can work on my truck anyday

 

Very nice man! This is exactlly how im setting mine up to run. Got my harness built, PCM triggers run. Just waiting on my raddy, alt and fans to get here. Tuesday is the magic day.

 

Very nice work. that is some what what I want to do when I put some one my truck.

 

Nice! Very nice!

 

Thanks for the compliments, it was a fun project and pretty cheap.
Fans = $120
Metal = $10
Relays, sockets, fuses and wires =~$30
Paint = $10

 

that's pretty nice