hi
-87 T/A digital dash problem.

I have this problem that my digital odo/trip-meter is fading out seconds after I turn on ignition.
so I have started to search for a failure.
to this display there is 8 conections on the print board. when you have the display aginst you I have so far found the signals to be like this.
pinout:
1 - 5v
2 - 5v
3 - 12v
4 - ?
5 - ?
6 - 12v
7 - ?
8 - ? probably ground and shield


As you see some off this is marked ? this one I do not know what they are.
I am at the moment unable to measure also. all my wireing is not hocked up.

do anyone know if my measure (so far) is correct? and can anyone find the rest off the signals/pinout.
then I can create a test bench to find the failure.

thanks to everyone that helps