I'm working putting factory power windows, locks, and mirrors from a 99 LS into an 02 W/T. I have the doors completely assembled with power window regulators, electric door latches, mirrors, harness, and door panels with switches. The plugs that go into the junction boxes at each end of the dash are plugged in as well.

There is an extra white two row long plug on each door harness that there is nowhere to plug into in the dash harness on the 02. I do have a complete dash harness with BCM available from the 99, but I was hoping to avoid having to swap all of that over. Is there any way to manually hook up a couple of wires to get everything to work, or am I stuck swapping the entire dash harness, and possibly the BCM as well? Right now the only thing that works is the Lock button. The unlock, windows, and mirror adjustments don't work at all.

 

I've been doing a lot of searching and it sounds like for 99-02 the dash harness needs to be replaced, but not the BCM. That's a bit of a relief, I was hoping I could avoid doing a reflash at the dealer. Still a PITA. Guess I should have done my research before offering to install this crap for $50. Sigh.

 

there a two ways. 1) swap dash wiring harness 2) run wires from each window switch and locks to each other and run a power and ground.

if you decide to do the second method. this thread shows what each prong on the switches do.
FSC - Chevy Truck Forum

the 99-02 dont run signal through the bcm like the 03+ on my 04 i switched everything from an 06 ext cab into it including the bcm. and everything works fine.

 

THANK YOU!!! I think I should be able to tap into those white connectors to accomplish what I need instead of going all the way to the window switches. You just saved me several hours of time and frustration replacing the dash harness.