I start my 2000 Z71 the dash gauges and shift indicator stop working. At the same time my tranny seems to be stuck in one gear and wont upshift or downshift. Then the service engine soon light comes on. The problem is intermittent because sometimes shutting down and restarting fixes the problem, but not all the time. I can go days or weeks without having any trouble then all of a sudden it starts doing it again. Checked all the fuses and checked battery cable all is fine. Could this be the ignition switch?

 

Well the ECU stores the code if it is intermittent so if you use a GOOD scan tool you should be able to pull it up. Shift indicator on an automatic? I would think it has something to do with the torque converter.

 

its your ingnition0 fuse

 

It definately sounds electrical since it affects the gauges... may also be a poor ground.

 

The most likely cause of this condition may be a loss of voltage to the transmission solenoid power supply circuit.
This condition may also be the result of an incorrect installation of an aftermarket electronic device such as a remote starter or alarm system.
Check the following items: [ol]With the ignition switch in the RUN position, test for battery voltage at the circuit fuse in the transmission solenoid power supply circuit.[/ol] [ol]If battery voltage is present at the fuse, inspect the ignition voltage circuit between the fuse and the transmission for possible opens.[/ol] [ol]If battery voltage is not present at the fuse, test for continuity between the fuse and the ignition switch. If NO continuity is between the fuse and the ignition switch, repair the open in that circuit.[/ol] [ol]If you have continuity between the fuse and the ignition switch, the most likely cause is the ignition switch. Replace the ignition switch.
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