Questions about E- Fans

**SS Smoke eater** · 01-31-2006, 07:22 PM

Ok, so I want to do the E-fans to my 2000 ecsb 5.3 From what I've read alot of people have done the LS1 fans because they are cheaper and for the most part easier intall except for the fabbing of the brackets. Anyways, the price for the LS1 fans are round 100 - 150 whereas the price for flexalite fans and other are like 380 or something. So, my question is what is this about the relay switch that you have to turn on with the a/c or do the fans come on automaticly???? Can someone shed some light on this subject for me please because I'm gonna be takin the truck into the shop very soon and would like to know about this so I can have the fans and new 180 t stat done. Thanks alot Justin

Also, If I am planning on doing a wait4me tune fairly soon, should I wait to do the efans and t stat or will it be ok to do the fans and t stat then get the tune??

**Aatcntrl1** · 01-31-2006, 07:49 PM

I think It's either Nelson Performance or Westers offer a wiring harness. I think it's a plug and play after that. I could be totally wrong. Maybe someone out there knows for sure. I'll shut up now!!!

**Colby 04** · 01-31-2006, 08:33 PM

Check with american auto salvage out of Ft. Worth, TX. They sold me my fans for $90 shipped - with a 6 month warranty. I have the LS1 fan harness from Nelson Performance - it made wiring them up very easy. The harness is designed to be controlled by your PCM - pin 41 I think. Pin 41 is not used and is not enabled on your stock PCM. So you'll have to have a custom tune done and have them enable the PCM to control electric fans. The harness comes with the wire with a pin attached to push into place. The harness is also equipped with a tap for the A/C...that way at least one fan will run when the A/C is on. I don't remember how much, but I think the harness is ~$90. Here's some more info

Good luck

**SS Smoke eater** · 01-31-2006, 09:04 PM

Thanks alot for your help Kolby, by the way, love your truck and as soon as I'm done with the performance mods, im doing the ss bumper cover, looks excelent on yours. Another question for ya... Since you said the stock PCm wolnt recognize the electric fans and harness, I need to do the custom tune. Well I'm doing that also, however, if I have the fans in b4 the tune, will they work because if I get them after the tune, I will have to send the PCM out again to be retuned...correct?? Im sorry for the questions but this is very confusing becuase one thing dosent balance with the other since the stock PCm wolnt read the fans and the fans wolnt work without the custom tuned PCM.....Thanks Justin

**Colby 04** · 01-31-2006, 09:43 PM

You can run the mechanical fan with the tune(PCM enabled to control e-fans). I did for a few days, I even called Jesse to make sure it wouldn't cause any problems. You need to get the custom tune, enabled to control e-fans - FIRST. After your vehicle is equipped with the ability to control the e-fans, then you can install them. If you install e-fans with the Nelson Performance harness on a factory PCM tune, they will not work properly, if at all. So do get the custom tune, then install the fans.

BTW, make sure you tell the tuner what thermostat you are running, 195, 180 or 160. They will set the turn on/turn off set points up for the right thermostat temp

**91_bowtie** · 01-31-2006, 09:53 PM

Originally Posted by Colby 04

pin 41 I think

You were close. It's pin 42

**BlownSierra** · 01-31-2006, 09:55 PM

i heard htat you can use a sensor tapped into your hoses to switch a relay. will this work? and whats the difference between aftermarket fans and the 2003 6.0 fans and the ls1 fans? and ive heard of people switching to 6.0 radiators as well? any info on this?

**Colby 04** · 01-31-2006, 10:03 PM

Originally Posted by t3k

i heard htat you can use a sensor tapped into your hoses to switch a relay. will this work? and whats the difference between aftermarket fans and the 2003 6.0 fans and the ls1 fans? and ive heard of people switching to 6.0 radiators as well? any info on this?

The new e-fans on the 05+ fit a 34" radiator, the radiator on the 04's and down is smaller - 28" I think

**Colby 04** · 01-31-2006, 10:06 PM

Originally Posted by 91_bowtie

You were close. It's pin 42

damn, so close. It's been a few month's since I installed mine...lol.

Jesse actually enables 2 pins, pin 42 and another one. The second one the A/C relay status or something. It's just another way of making sure at least one fan remains on when the A/C is turned on.