I have a 1992 GMC halfton. It has developed a Turn signal and dashlight problem. First, with the lights off I can turn the signal to either the left or right and the signal lights work, except the Dashlights flash on and off and the guages bounce as the signal flashes.

With the lights on I switch the turn signal to the left and the indicator on the dash comes on solid and the signal lights dont work.

I Have no idea where to start looking.

 

SOUNDS LIKE A BAD GROUND SOMEWHERE...look at the battery cables first