I'd start by rechecking the repair on the vss wire and while your down there pull the vss and check it electrically.
Spin it by hand while hooked up to a volt meter. If you get nothing, switch to ohms. Still nothing, you've got a bad vss.

The vss goes to pins 20 & 21 on the pcm.

 

Possibly they burned the PCM up when they shorted the wire.

 

SilverSurfer,
Does the VSS drive the spedo, if the VSS is not working the spedo won't work? Why would the brake and ABS lights be on, and why no codes? If the VSS was not getting a input signal /power from the PCM pulling it out and turning it won't tell us that the VSS is bad, correct? What PCM pin is for the spedo, also do you hace voltage values for the VSS and Spedo PCM pins?

Thanks.

 

Possibly they burned the PCM up when they shorted the wire.

ASTE25,
Wan't to eliminate anyother possibilities before condeming the PCM.

Thanks.

 

Doubt a shorted vss would smoke the pcm. The diagram I was looking at didn't specify voltage, but it's just signal not power.

The reason for the abs and brake lights is the wheel sensors aren't matching up with the vss, so the pcm responds by throwing warning lights. Some cars disable abs and trac control if the ck eng light comes on.

Oh yeah, the wire colors for the vss are lt green/black and pink/white. Those are the colors at both ends, if that's not what's going to the vss in question let me know what you have and we'll figure out what that actually goes to.

 

if the spedo went out would it cause the VSS problem, or does the VSS supply the reference signal to tthe PCM to work the spedo??

 

Doubt a shorted vss would smoke the pcm. The diagram I was looking at didn't specify voltage, but it's just signal not power.

The reason for the abs and brake lights is the wheel sensors aren't matching up with the vss, so the pcm responds by throwing warning lights. Some cars disable abs and trac control if the ck eng light comes on.

Oh yeah, the wire colors for the vss are lt green/black and pink/white. Those are the colors at both ends, if that's not what's going to the vss in question let me know what you have and we'll figure out what that actually goes to.

I will check tomorrow and back to you with what I find.

Thanks

 

OK The problem is fixed. There are three VSS sensors on the transfer case, they are in a straight line from left to right. The one causing the problem was the center one, and the sensor was good. The wiring to the sensors is not a straight run to the PCM, there are two connectors, one low to the sensor wiring and one up top to the PCM, it is a two nwire connector. SilverSurfer the wire colors that you gave me did not match the truck wiring nor did the wiring diagram I have, both were different . the VSS wiring was a GRN/BLK and a PPL/Blk. ann OHM check of the wiring from the VSS plugs to the PCM showed 0 OHMs. The problem was in the lower connector. I cut out the connector and soldered the wires and the problem is gone, everything back to normal.

I want to thank you for your and everyone else that replied.

 

Awesome! Thanks for updating the thread, hopefully it helps someone in the future!

 

Good to hear you got it fixed.

 

i have same exact problem, although mine is an 04 2500HD 6.0. will the same repair apply to my truck. just a thought befor i get started. thanks flyenfloyd

 

You said nothing about the history on the truck. Have you had any work done on the tranny or transfer case? You can try following the advice on this thread. Good luck, let us know what you find.

 

I know this Is an old thread, but while working on my 2000 Silverado with similar issues I cannot find a diagram from pcm to the main plug and vss to begin diagnosing my issue.

 

I know this is an old thread but I am sure others will find it when they have the same problem. I fixed my VSS aBS and speedo problem. The VSS is on the tail end drivers side of transfer case. my problem was caused by the VSS wire connector. If you follow the VSS wire it goes into a junction of wires and then continues forward almost on top of the transmission. Half way to the firewall the VSS wire goes into a connector with two female ends(joining the wire from the vss with the wires going forward to the PCM.. The connection nearer the firewall, pcm wire connector some how got loose. I checked grounds and was getting ready to chase a broken wire. If i had seen a number of postings it points in some cases to a connection that worked its way loose.

this url talks about diagnosing the problem and has good diagrams of vss location and wiring diagram for vss sensors https://www.performancetrucks.net/forum ... on-484619/

There is also a short youtube video showing a connector. I cant find the url right now but think it was done by jeep wagoneer or something similar.

 

Here is you tube video showing a good video of the connector. My loose connector was on the firewall side and not visable in the video.

 

I'm have the same problem no power to any t-case plugs followed wires up to fuse box and pcm no power up there don't know where to go from here