Switched Power tap 2011 Silverado 1500 WT

Discussion in 'GM Electrical Tech' started by Dave D., Mar 2, 2011.

  1. Dave D.

    Dave D. New Member

    Having transmission issues (harsh 1-2 upshift). GM concerned about my installing fog lights a couple of months ago. I had consulted many forums before deciding on a power tap. Is it possible I caused damage to my transmission?

    Attached Files:

  2. Dave D.

    Dave D. New Member

    Note that this switch feed is only to operate a relay and I fused it at 3 amps. Any one know if this could cause an issue with the common bus? Tranny? thanks
  3. silveradotrailblazer

    silveradotrailblazer Epic Member 5+ Years ROTM Winner 5000 Posts

    Never heard of such a thing, pure BS. Try disconnecting the fog lamps from the power source and see if the problem go's away.
  4. troutbug

    troutbug Rockstar 100 Posts

    That's the first time I've ever heard anything like that. Sounds to me like your dealer is trying to postpone or get out of having to do any service work for your new truck. Like silveradotrailblazer said....BS!!
  5. stephan

    stephan Rockstar 4 Years 5000 Posts

    I can't read what you're tapped into. If it says ign. accessory, or auxillary etc then you're good, & it's like STB & Sal say above, & GM just doesn't know what the problem is, so they're blaming your wiring.
    The only places I can think of that you wouldn't want to tap into would be the speed sensor, rpm sensors, tach etc as your lights could suck amprege out of the circuit & cause them to give false readings.
  6. Taddpole

    Taddpole Member

    I think their rooster pooping you. I think the common bus their talking about is the common data bus. Thats the common data line that all the computers talk to each other on. Not the common switched power. What you did would'nt have any to do with the trans. I think you said on you're other thread that it was fine for 2 months. Keep after these jokers and make them fix the problem or try another dealer. Good luck with this.
  7. Dave D.

    Dave D. New Member

    Thanks for the responses. I will be doing a lot of research this weekend. The access point is an unused connector, maybe called Body Control Module 3. I have no options, so it was likely for power doors, heated seats, power windows or something. So far here is what I have found, while I believe the common bus for tranny is linked to the other components like the oxygen sensors etc, I don't see a connection to the Body control bus. What I have learned is, when you operate a relay for aux lights or whatever, when the lights are switched off, the relay selenoid develops a voltage spike and arcs back (maybe as high as 150 volts) across the on\off switch into the 12Volt source wires that may also be used as a Data communication link. So now I am researching on "Snubber Diodes" which are placed accross the Selenoid coils to allow this voltage spike to be eliminated. Problem with this theory is, I installed 55 wat fogs (if you have fog light option they are only 25watt) and thus I only use them during foggy conditions or Snow Storms which I encounter going to camp once every two or three weeks. Like I have used the fog lights 5 times in two months. Anyway, we will see what happens on Monday. Disconnecting the Fogs has had no effect on the condition.
  8. gotohatteras

    gotohatteras New Member

    Problem is the transmissionsssssss....not just yours. They know they have a problem, just don't want to admit it.
  9. zigger215

    zigger215 Member 2 Years 500 Posts

    Lol as long as you aren't FEEDING that circuit anything but rather just drawing whatever it can give then you should be good. Typical GM dealers...dicks. They make it hard to be a diehard GM guy.

Share This Page

Newest Gallery Photos