I bought this vehicle with 40,000 miles about four years ago. It now has 60,000 miles. It has been a great truck. Only three things I have done to it besides change all the fluids and regular maintenance. Has been put a new water pump, new front brakes, and a new battery. Shortly after I bought it I installed a new stereo. One day about two months ago, driving down the road when I notice the speedometer not working along with the odometer. A couple days later I decided to check all fuses. Nothing. Next I changed out the VSS and the connector going to it. Nothing. A few days later it started to work? As I kept driving it stopped working. So I got home and pulled the dash apart thinking it might be the cluster. Unplugged the cluster and plugged it back in several times. Each time the speedometer needle moved and then went back to zero. I also checked the connection and it looks great.( I have been driving the truck almost every day and sometimes it will work and sometimes it wont. I tried hitting potholes in the road to see if that would do anything like jar something loose) Thinking that the cluster is just fine, I read that it could be a connection to the stereo. Pulled it all out and checked the connections and everything looked just fine. I thoroughly and visually inspected the engine compartment for anything out of the ordinary.
A retired GM Mechanic that I know lives down the street. He had a scan tool from GM and did a full diagnostic on the truck. No codes were thrown. No dash lights. He programmed the PCM back to factory settings. He said that there was no signal from the BCM. Everything else looks perfect. I did not want to take to much of his time since this could take a while to exactly pinpoint what the problem is. The speedometer has been working less and less. Thinking this could possibly a wire thats grounded? One of the control modules? I have hit a wall. Any help would be great. Thank you
Wednesday, March 6th, 2019 AT 2:27 PM
(Merged)
