Oh, no, what else can go wrong?

Got the trans-control working just fine, controlling the trans, now, I've totally lost the speedometer. Initially, when I simply piggy backed the 2 original speedo wires to the new purple and black wires from Quick 4 to the VSS sensor on the transfer case, I had a working speedometer, but had bad codes showing on the controller display. That was on the day that I had practically nothing else hooked up, including the crankshaft sensor. Now that's all fixed, but. -- Today, I went through every combo of hooking up the two wires to the Quick 4, including one wire from the speedo to a dedicated ground and the other to first one, then the other of the output wires to the Quick 4. Nothing worked. So, to check the speedo, and, or the VSSB, I cut the 2 Quick 4 wires and hooked my speedo wires back up to original - green/green and purple/purple. No speedo!

What did I fry in the speedometer, or the VSSB? Something sure changed. I think I may have a schematic of how to trouble-shoot the VSSB somewhere in a Helm manual, or something, but right now, I find myself in an area that has the potential of costing $ and being out of my area of expertise by a good margin.

Anyone with ideas for me to start checking?

Thanks, DW

No joy, so far. Have the VSSB out and tried to "bug" it, to no avail. Took it to the Chevy dealer and they can't check it off-vehicle. I do know that I'm getting a good AC voltage signal from the VSS, all the way to the VSSB. Isolated the volume/speed wire to the radio, without any change. Checked the brake fuse (10A) and another referenced 10A fuse at loc. 4, both good. Can't find any open, or grounded wires.

Any way to further bug out that VSSB, and, or move on to the speedometer?

Right now, I'm about ready to wrap up the install and drive without a speedo/odometer for the rest of the time we're here, before Texas. Come next Summer, I'll have to have an odometer reading for inspection. So, still hoping for some resolution, cuzz I ain't about to give up on the old Suburban. Just about the best vehicle I've ever owned.

Think I'll pop the instrument cluster out of there and see if I can find that green wire from the VSSB. Anybody know what kind of signal/voltage I should be seeing there. Running, or with only switch on?

Thanks.