Activating PCM for EFans

[Rocket Man]

I know a tune from BB can take care of this but I don't want to spend money on that right now. I will eventually do a EFI Live tune since BB doesn't come out my way for an in-person tune but it will have to wait. However, I do want to buy a Doorman fan and also a cable and overdrive alt pulley from LS1 Fans. My A/C sucks in traffic and sometimes turns off and I'm hoping this will help, as well as provide other benefits. I've heard a dealer usually doesn't know how to or can't do this. Is this something a regular mechanic can do or am I screwed?

 

[YukonXL04]

The dealer can do it, but some just don't know how. I spoke with my local dealer service manager and he was clueless. I even told him how to do it but he wasn't confident they could. He told me they would charge me an hour of labor and attempt it lol... I just waited till I got my tune...

Yes the fans help with your ac when stopped and in traffic. Mine stays ice cold all the time.

Edit: yours is a 02, so you can do the ac trigger wire instead right?

 

[Rocket Man]

Edit: yours is a 02, so you can do the ac trigger wire instead right?

I'm not sure so anybody have an answer? I've heard to get the most benefit I need the PCM controlling it.

 

[YukonXL04]

That is true, and I believe there is still a way for you to use the pcm. But I belive it requires repinning some stuff on the ecm. Search around some and you'll find it. I believe there is some threads in the tech section

 

[Rocket Man]

Yep, I've read everything in the tech section on it. The harness that LS1fans.com sells for the '99-'02's hook into the PCM and this is what they state: " * You must have your PCM activated or tuned to take advantage of the trouble free OEM operations of the fans. By doing so the fans will operate in your truck exactly as they do in the Corvette, Camaro and Firebird. The fans will have the ability to operate in 2 fans high, 2 fans low and a single fans high depending on the demand read by the PCM." They sell 3 different harnesses for my year- for universal fans, F Body Camaro-type and '05-up Truck/SUV Factory or Dorman replacement fans. I plan on buying the Dorman 620654 that's spec'd for a 2005-up SUV and the corresponding LS1fan harness. I just need to find someone to activate my PCM. I've read that the harnesses you can get that just tie into the A/C wire and use thermostats aren't that good.

 

[LabGeek24]

Just go ahead and get an autocal and get BBP to tune it! You'll love it and plus they'll activate your ECM

 

[YukonXL04]

Yep, I've read everything in the tech section on it. The harness that LS1fans.com sells for the '99-'02's hook into the PCM and this is what they state: " * You must have your PCM activated or tuned to take advantage of the trouble free OEM operations of the fans. By doing so the fans will operate in your truck exactly as they do in the Corvette, Camaro and Firebird. The fans will have the ability to operate in 2 fans high, 2 fans low and a single fans high depending on the demand read by the PCM." They sell 3 different harnesses for my year- for universal fans, F Body Camaro-type and '05-up Truck/SUV Factory or Dorman replacement fans. I plan on buying the Dorman 620654 that's spec'd for a 2005-up SUV and the corresponding LS1fan harness. I just need to find someone to activate my PCM. I've read that the harnesses you can get that just tie into the A/C wire and use thermostats aren't that good.

Yes, but because yours is a 02 your harness will have a wire you have to tag into the ac compressor harness and one that goes to the pcm. 03+ both wires go to the pcm.

 

[Rocket Man]

Yeah I saw that. Thanks. I went ahead and ordered the fan and harness today as well as the overdrive pulley, now I just hope I can get someone local to activate the pin in the pcm. I don't want to spend another $600 for the EFI Live tune right now. The fan, harness and pulley were less than $300 which I feel is a good price.

 

[Tiki]

Talk to a local tuner, they'll have similar capabilities to BB.

 

[JennaBear]

We do offer a fan only tuning option.