4L80E No Shift

[six5turbofan]

We have a 1994 Suburban 6.5TD "F" 4L80E
It pulls out in first never upshifts at all. No speedo reading so I'm figuring VSS maybe, but will that cause no upshift at all ? I know I need to buy a scan tool so I can start looking at all the info available...
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[Scrufdog]

check codes, check/replace VSS, and check fuses.

[six5turbofan]

The only code I pulled out was a 81 (I think) ABS which the ABS light does come on due to no VSS. When checking ABS codes I got a 28 or 38 I think it was, it just said there was a difference in wheels speeds or something like that. We just have a cheap code reader I need to get a good one....

[six5turbofan]

Wire was pulled out of the vss on the transfer case. Speedo and trans both work great.