Check to see that all your turn signals, running lights (orange lights up front) and brake lights work when activated and flash at normal speed. Could just need a bulb replacement. Those bulbs are known to look good, filaments are not broken, etc, but still need replacing. If rear brake lights do not work, but 3rd brake light (at top of hatch) works, could be a short or ground issue on one or both rear circuit bds. (tailight assemblies). Check fuse first of course, but probably a short. Make sure that your plug in harness connector hasn't shorted as well, as my 97's did. Both rear brake lights out, only third brake light on, as well as ABS and TCS idiot lights on. If you buy new cicrcuit bds only to solve your problem, goop weatherproof silicone caulk over the connection on both sides once you prove it works to prevent this shorting out from happening again. Design flaw by GM. Who would ever place any connection in the direct drain path of the rear hatch. The other option you have which costs about $5 is to label the harness wires that plug into the circuit board as to their location on the mating plug, cut the plug off the harness, attach connectors to each wire, cut down all 4 sides of the circuit bd plug about 3/8th to 1/2 in exposing the 5 pins. Be sure to clean off the shorted middle, thin prong/pin carefully. Attach the mating connector from the location markings you did earlier. Test the brakes, notice that your ABS/TCS dash lights are now out, and apply weatherproof silicone to the connections so that water, etc cannot collect at the harness or connections. The McGyver way, but my circuit has worked for over a year incident-free. Any questions, email me directly at
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