Our 04 Envoy had a recall on turn signals and tail-lights, they just had to replace a relay. I would check with your dealer to see if your vehicle has been recalled.
Yes.
Most likely turn signal flasher
head lights won't work, no power to them, signal works , reverse lights work
There is a relay in the trunk (left hand side wall) that may have been burnt. You may want to check this out...had the same problem with my 1992 Camry.....different year of course. The wires to the running lights were broken and exposed, caused a short, which in turn burnt the relay in the trunk.
The cause for a turn signal flasher to keep clicking on a 1999 GMC Jimmy is a bad flasher unit. Replacing this with a new flasher unit should solve this problem.
have you checked the fuses?
fuse, bulbs
brake light switch would be most common cause
emergency blinker
Most likely poor wiring.
check fuses
It can, if you leave the lights or flashers on too long.