Results 1 to 10 of 10

Thread: e fan wiring and control

  1. #1
    Senior Member
    Join Date
    Feb 2008
    Posts
    145

    Default e fan wiring and control

    ive got a 01 silverado 5.3 with cos3. trying to get pin 42 to controll my fans but it just stays on. i can go into the scan tool and turn them on and off and nothing happens. not useing fan #2 just one any ideas

  2. #2
    Senior Member
    Join Date
    Feb 2008
    Posts
    145

    Default

    this is my tune that both 42 and 33 stay grounded untill you shut the truck off anybody
    Attached Files Attached Files

  3. #3
    Senior Member
    Join Date
    Aug 2007
    Posts
    126

    Default

    did ya try a full flash after changing? Maybe the settings didn't take. Only thing I could think of is a wiring issue with the relays, pcm looks ok as far as programming. Pin 42 on blue connector is your fan #1, but probably stating stuff you already know.

  4. #4
    Senior Member
    Join Date
    Feb 2008
    Posts
    145

    Default

    what do you mean by full flash all i ever do is hit the red arrow in the center. the wires are staying grounded hooked up to relays or not thats why in confused.

  5. #5
    Senior Member
    Join Date
    Aug 2007
    Posts
    126

    Default

    okay full flash is the red arrow all the way to the right. you have the green read arrow center red calibration flash and then the right full flash red arrow.

    The pcm will ground the relays so pin 85 on the relay should go to the pcm and pin 86 go to 12v power. That is the coil terminals in the relay. terminals 30 and 87 on the relay are the contacts.
    Last edited by chevy052500hd; July 22nd, 2009 at 08:28 AM.

  6. #6
    Senior Member
    Join Date
    Feb 2008
    Posts
    145

    Default

    yeah i know how the relays are set up but my thing is the ground coming out of the pcm is staying grounded and never turns off untill 5 sec after you shut the truck off i put my old tune back in it and it stays grounded on that one as well then i went into the scan tool and tried to turn the fans on and off that way and it gave me a unable to connect box so i tried the ac compressor on off and that worked so wtf am i doing worg i only need control of fan 1 not 1 and 2 but ive tried both ways and the same thing every time is there another pin i should use or just 42 and 33 cause neither of them change from being grounded

  7. #7
    Senior Member
    Join Date
    Aug 2007
    Posts
    126

    Default

    try maxing out G0903

    I also noticed on a/c pressures for fan 2 were not matching with fan1 try matching the two 3447 kpa see if that helps

  8. #8
    Senior Member
    Join Date
    Aug 2007
    Posts
    126

    Default

    only other thing is try a full flash and see if that fixes it otherwise may possibly be a pcm issue.

  9. #9
    Senior Member
    Join Date
    Feb 2008
    Posts
    145

    Default

    ok i got it my meter was lieing to me so after adjust the parameters and hooking it all back up it works thanks for all your help

  10. #10
    Senior Member
    Join Date
    Aug 2007
    Posts
    126

    Default

    cool

Similar Threads

  1. N20 Switch wiring with OS5
    By BowlingSS in forum Custom Operating Systems
    Replies: 9
    Last Post: August 14th, 2009, 12:50 AM
  2. Plx wiring help
    By blazinblue in forum General (Petrol, Gas, Ethanol)
    Replies: 1
    Last Post: September 28th, 2008, 07:53 PM
  3. 01-02 to 03-04 cpu wiring and programing
    By woody69 in forum E37, E38 & E67 PFI ECM's
    Replies: 0
    Last Post: August 1st, 2007, 05:47 AM
  4. Need Help Wiring up Sm-AFR to V2
    By Chalky in forum General
    Replies: 3
    Last Post: March 11th, 2007, 05:36 AM
  5. wiring
    By 69camaro5speed in forum General (Petrol, Gas, Ethanol)
    Replies: 2
    Last Post: January 27th, 2006, 06:05 PM

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •