Ken K
I'm Awesome
Your fuse relay center actually uses PED push to lock terminals. With looking at the connectors cavity with a fuse removed, see the open window next to the terminal? It's a plastic tab that falls into the terminals void. Using any tool that will fit, gently lift up the terminals wire from behind (This helps release), then push the small plastic tab away from the metal terminal towards the open slot. Pull the wire from behind and it will slide right out. At the bone yard, you can grab some of these with some wire like 12-14 AWG (ORG), (PNK) and cut off a length. You can solder these onto the wire with some insulation peeled back, careful not to cut strands of copper wire as that reduces the cross-sectional diameter, reducing the current flow ability. Liquid tape is now your friend as there is no good way to use shrink tubing and you do want it water tight soldered joint.
The single 50amp relay will work, but the illustration from earlier, looks like the vertical tabs on the side of the fuse relay center will accept relays with the exterior slot on the back side. You could grab those in the bone yard too. Just wire them up, use some dielectric grease, provide a good ground and don't forget the terminal that goes into the VCM/PCM (Cavity 9 / DRK-BLU). If that wire is already there, chances are the VCM/PCM will provide ground when hot or with A/C. I would bet that A/C fan operation is using a pressure switch that signals the VCM/PCM when high A/C pressure reaches 240 psi. It may be ready for a relay and proper power to get going. I went back and looked on GM eSI, it make no distinction on your "RPO" code found on the glove box lid, but since you have a towing package, it may already be programmed to work. If there is a Dark-Green wire in the VCM's connector, follow it back to the Relay/Fuse box center. It is common to use one harness and the wire is already in it, just cut and taped inside / under the fuse box.
I purchased many tools thru the GM dealer, but was also at one that was going to auction, bought the rest there, so I have enough electrical stuff over that last 30+ years, I have an entire SnapOn tool box dedicated to everything electrical...including a chrome "Tach/Dwell" meter and 6 distributor wrenches. Hope this helps!
ASE Master Tech since 1978 / Retired ACDelco instructor.
P.S. Good fuse box photo, well done!
The single 50amp relay will work, but the illustration from earlier, looks like the vertical tabs on the side of the fuse relay center will accept relays with the exterior slot on the back side. You could grab those in the bone yard too. Just wire them up, use some dielectric grease, provide a good ground and don't forget the terminal that goes into the VCM/PCM (Cavity 9 / DRK-BLU). If that wire is already there, chances are the VCM/PCM will provide ground when hot or with A/C. I would bet that A/C fan operation is using a pressure switch that signals the VCM/PCM when high A/C pressure reaches 240 psi. It may be ready for a relay and proper power to get going. I went back and looked on GM eSI, it make no distinction on your "RPO" code found on the glove box lid, but since you have a towing package, it may already be programmed to work. If there is a Dark-Green wire in the VCM's connector, follow it back to the Relay/Fuse box center. It is common to use one harness and the wire is already in it, just cut and taped inside / under the fuse box.
I purchased many tools thru the GM dealer, but was also at one that was going to auction, bought the rest there, so I have enough electrical stuff over that last 30+ years, I have an entire SnapOn tool box dedicated to everything electrical...including a chrome "Tach/Dwell" meter and 6 distributor wrenches. Hope this helps!
ASE Master Tech since 1978 / Retired ACDelco instructor.
P.S. Good fuse box photo, well done!
