Speedometer and Odometer Not working.

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6uillermooo

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My speedometer was working and while driving It went up and down and stopped working. I replaced my VSS and issue remained the same. I also tried to replace the pig tail connection but the new connection came with a purple and black wire while the one on my truck had a black and green wire. I connected black and black and the other 2 together and issue remained the same. I ordered the correct pig tail so. My question is did I wire the connection wrong or could the speedometer issue be the stepper motor because I had a similar issue with my fuel gauge being bouncy and I replaced the stepper motor which fixed it. Any feedback helps
Please help me guys.
 

Schurkey

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WHAT VEHICLE???

When that was my '88 K1500, it was the circuitry in the instrument cluster.

Replaced the VSS, no difference. Replaced the speedo, no difference. Finally replaced the instrument cluster, re-using the original speedo. Problem solved.

The symptoms for me was an intermittent speedo--it'd work, it'd quit, it'd come back to life in a couple miles...or a couple days. Sometimes whacking the dashboard with my fist would get it to work again. When the speedo quit, the odometer, cruise control, ABS also quit; and the Check Engine light would come on.

But if you've got stepper-motor gauges, your truck must be newer than mine.
 

Ruff Idol

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WHAT VEHICLE???

When that was my '88 K1500, it was the circuitry in the instrument cluster.

Replaced the VSS, no difference. Replaced the speedo, no difference. Finally replaced the instrument cluster, re-using the original speedo. Problem solved.

The symptoms for me was an intermittent speedo--it'd work, it'd quit, it'd come back to life in a couple miles...or a couple days. Sometimes whacking the dashboard with my fist would get it to work again. When the speedo quit, the odometer, cruise control, ABS also quit; and the Check Engine light would come on.

But if you've got stepper-motor gauges, your truck must be newer than mine.
I'm in the same boat right now with an intermittent speedo. In your case with an '88 the VSSB unit would have been built into the cluster and that's why a swap worked. Since I have a '92 in my case the VSSB unit is separately mounted, behind the glove box. So far I determined there is a 12V+ power issue, NOT ground as I'd expect, to the VSSB as yesterday I supplied 12V with jumper wires to terminals C8 and C9 on the VSSB, and as soon as I took the truck for a spin with this rigged up my speedo worked perfect the whole trip. While still driving, I disconnected the ground and it STILL worked. So there is a 12V ignition source somewhere that is bad (I don't think there is a fuse for this, maybe power comes right from junction block on the passenger side of the firewall?)

OP, since you have a '95 I believe that was the last year of the separate VSSB unit in the glove box. You could perform this same road test and see if it comes back. If not, you likely have bad circuitry in either the VSSB or ECM as those are the last links in the chain before a final, pulse-modulated signal leaves the ECM and goes directly into the speedo via the inst. cluster wiring harness.
 
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