upfit wiring questions

shenandoah75 · August 1, 2012

i'm trying to find some power sources for some aux stuff i'm putting in.and i've got several candidates already. I've got the desired circuits and fusing identified on most potential options with the exception of UPFIT 4-WAY CRM. Been through the power distribution pages many times (and i admit i'm looking at an 2003, not an 2005) but where this is coming from?

If i have it right ( i have a note from a couple of years ago when i was looking for a feed for RV rear view cam that has the following documented::

1) with ignition off: Ground is bottom right... I measure 12V, 6V, 6V between the other three pins and ground.

2) with ignition on, pin assignment seems to switch and i get ground on lower lfet / upper right (i'm skeptical on this cause my notes are a bit off). I can double check tomorrow...

Main question is whether anyone tell me where they are fed/fused from? If pin reassignment is occurring, i'm assuming there's got to be a relay involved? If i were to use this four way, is there a standard adapter i can use? Any other tips appreciated.

thx in advance

-brad

SoCalChris · August 1, 2012

I'm assuming that you're talking about using the upfitter connections down by the pedals? I used that for my CB radio, and as the amp turn on lead for my truck. You can buy the plug harness from the dealer, IIRC, mine was $40-$50. I don't remember the part #, but any decent parts counter guy should be able to help you.

Have you looked at the gmupfitter.com site? They've got all sorts of wiring diagrams that may help you. For a 2003, I would look at page 199 of this document. If that doesn't help you, here's a directory of other upfitter documents that may help. Good luck!