Not Shifting Gears, Speedometer Not Working Either

[nyris221]

95 GMC Sierra Extended Cab

 

So I have been playing around with the audio in my truck for awhile. Today I started up my truck and I get on the road and my rpms are high and its not shifting into 2nd. I noticed the other NIGHT when I turned my lights on the beeping noise stayed on. The noise like when your door is open and such. So I am lost. Ive taken the dash peice off numerous times and no luck. Please help me fast!

[GM-Tech]

No speedo and no shifting means you've lost the speed signal. I don't remember '95 specifically, but I believe the speed sensor in the trans feeds a buffer first, which then sends a signal to the cluster and the PCM (for trans operation). The buffer is a small box about 3-4" square and about 1/2" thick. It might be white plastic.

 

It's been a while, but I believe it's way over on the right side of the dash, behind the kick panel, but it might be directly under the dash. This has a power source, so if you've blown a fuse (no idea which it is), that may be the problem.

 

The lights on warning is a different problem, but could be related to some wiring damage that might have been done.