blinkers & turn-signals stop working

[CCAddict]

2001 convertible. Both turn-signals stop blinking when heater or a/c is on. Unpredictable, but inevitable. Blinkers stop blinking on dash and both turn-signal lights do not go on. Got angry honk behind me when it happened the first time.

Need to pound really hard on dash in order to get the things to work again. At 60 mph it's hard to do, as seat belt cinches me back. It will continue flashing for duration of turn or lane change, until the next turn or lane change when I have the slam the dash again.

It's ridiculous. I'm surprised that a car priced at 60K has such a flaw in it. It's dangerous and horribly annoying.

Any suggestions on how to fix it? (aside from paying $125/hr to a shop?) Could it be the flasher, or is there a relay of some sort in there? Or the contacts? And where is it located? Has anyone else have the same problem? From what I was reading, several chevy cars have this blinker problem.

[Junkman2008]

The problem is your hazard switch. It has went bad or the contacts on the switch are too dirty. The next time this happens, push the hazard switch button rapidly a bunch of times. This will temporarily fix the issue and your signals will start working. At this point, you have 2 choices. Replace the hazard switch or bypass it with the hyperflash bypass cable. Cost wise, either solution is the same if you do the labor. The bypass harness is real easy to do. Hazard switch is a lot more work. Either will solve the issue. It's a known and common failure with the C5.