95 Silverado stall w/lights on

[speedy Keith]

Hello i have a 1995 Silverado it will stall if you have the head light on and put the truck in drive. If I turn on the lights parking or head the truck will run rugh and will stall even worse if you step on the brakes. I have replaced turn signal switch, Brake light switch, alt, rear light bulbs and cirit bords,friunt turn and run bulbs removed all and i do mean all the ground cleaned or replaced them. when you have the lights on and use the turn signals all the lights will blink in the back and the plate light will do the same. The one thing is it will goaway some times and the truck will run grate as long as i dont use the turn signals. Help















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