All my instrumentation gauges and gear select and mileage indicator quit working but there is still power on the cluster as the back lighting still works and service light still is working (has been on for some time and unrelated issue). I checked all fuses and there OK. What I find odd is I can plug a scanner in my obd2 port and the all gauges work like intended and accurate I can also drive down the road and all work including tach and speedometer. I am puzzled with why it works when scanner plugged in only. Any ideas or help would be greatly appreciated. Thanks

 

It sounds like the scanner is completing the electrical circuit in your car. I would start off with checking the battery and alternator first. If anything is off, even slightly.. I would replace it.

 

I have a 1999 GMC Sierra 6.0 that is having the same problem cluster works when scanner is plugged in. Did you ever figure yours out or can anyone help me please?