HI THERE

i am a loss on how to proceed with troubleshooting my vision microsystem fuel gauge

any help would be appreciated:

1, complete VM 1000 operation manual
2. complete installation manual for VM1000
3. thoughts on failures that might cause the system to work in general, but
      not the fuel quantity portion of the system
4, spare system(s) for sale

we have rung out the wires and that seems OK
we have replaced the panel gauge
we have checked the 26 wire ribbon cable

the panel unit briefly flashes when turned on then nothing

BY THE BY
it is useful to know how much fuel is in each tank; in this airplane there was a nightmare that we removed.

    THE BUILDER HAD PUT A HIDDEN FUEL SELECTOR BYPASS,  SOMEWHERE ALONG THE WAY
        THE VALVE OPENED AND WAS FEEDING FROM BOTH TANKS AT ONCE.
   
 hard to know without a fuel gauge  
                                      WE REMOVED THE BYPASS

help please

thank you in advance

peter