Hello - I am looking for some input here. The situation is as follows:
The speedometer does not work on my 1993 Toyota Corolla DX 1.8L. It stays at 0Mph until probably 40-50 Mph and then shoots up to about 67 and stays there whether you go 80 or 50. Another strange thing is that the clock hours count 1,2,3,4,5...12. And keep cycling. I was told that the circuit that the clock and the speedo run off of is completely separate, but they both went out at almost the exact same time. (if not, within a day or so).
Troubleshooting performed is as follows:
Today I removed the speed sensor from the transmission. The gear wheel on it moves as I think it should feel. There is no wear on the gear, nor is there any wear on the gear inside of the transmission. I removed the insturnment cluster today and looked at all the connections. They didn't appear to be dirty, but I used a Q-Tip and some Alcohol and cleaned all the connections. I removed the front cover of the housing and the speedometer moves as it should (I can move it to wherever, and it moves back down at a set pace/resistance.)
I am wondering what the problem might be? It sounds like a potential ground somewhere to me, but I cannot be sure since I don't have such detailed wiring diagrams to diagnose this.
Has anybody heard of anything similar, or have any recommendations as to what to try next? I really appreciate your input. Thanks!