GMC Troubleshooting Questions? Ask a Mechanic for Answers
Cam is either offline or away, might I be of assistance.
The first thing to do is obtain a wiring diagram of that circuit, so I will need some more information in order to look that up.
Is this the sub-model WT, SLT, SLE, etc and which engine came in this, the 4.3, 5.3, etc and is it gas or flex?
One more thing, is this the base or up level power doors/
Anyhow, here are all of the power door lock wiring diagrams, start by checking the fuses.
I will be back in just a moment.
Ok, be sure to let me know the results.
Did you actually test both sides of the fuses using a voltmeter or at least a 12 volt test light?
If not, that would be the next step, and continue testing fuses when asked and not just looking at them.
You say there is no power to either side door controls. May I ask which color wires have no power?
It's possible there is one of those 3 relays that are bad. Hopefully we can figure it out by the results of a few tests.
Also, if you have a scan tool it may save us some time to retrieve the codes from the bcm.
Ok, once you know the color of the wires, let me know and if you have any spare relays in either fuse box, also let me know if you swap any relays.