HVAC wiring issue

[Dan-95Tahoe]

Can anyone tell me where the grounds are for the HVAC system on a 95 Tahoe?

The whole system quit working, so I replaced the HVAC controls. Not the issue. After some investigating, this is what I found:

1. The blower motor is good, and there is juice to the purple wire at Low, Med1, and Med2. No juice at the high setting. The black wire at the motor has no ground.

2. The high blower relay is good. All the wires checked out except the ground wire, and again no ground. So that explains the high setting.

I'm assuming that all these HVAC items share this bad ground, and that is the root of my problem. Do these all share a ground? Can I simply route new grounds for the blower motor, relay, and etc. to fix the issue? Sorry this is so long.

Thanks

Dan