Probably the turn signal/hazard flasher went bad. On some vehicles they are separate units, but on some vehicles they are the same unit.
I also have a 2002 Chevy Malibu that had the weird blinker issue. Last year I checked it out and found it was a recall. You should be able to have it fixed for free. Mine was fixed last spring and I haven't had any problem since.
Just had my turn signal switch replaced, for the second time, on my '98 Chevy Lumina. I paid $260 to a fairly trustworthy auto repair mechanic
Just because I had one in the past (2004 malibu) I would say that I has something to do with the fuse that works for the turn signal and brake light. Because for them both not to be working I would doubt that it was a bulb. Just my opinion. Of course you should get it looked at.
If there is a recall your Chevy dealer can help you. You can also look at the link I will post.
change the bulbs and fuses
The turn signal flasher on a 2008 Chevy Avalanche is located inside a panel close to the gas pedal.
turn signal switch needs replaced!
See answer for same question on 2004 Chevy avalanche. JIT
It is combined with the hazard flasher module
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You're going to have to change the hazard light button on the dash
It's right up in front on the dash. It's part of the hazard switch.
Yes
The Chevy Avalanche was "started" to have an option for both an SUV and a truck. The avalanche is both. It has the versatility of an SUV, but a bed of a truck.
The hazard switch and the turn signal and brake lights are all incorparated, chances are the 3-1 switch is broke internally check all fuses
see your dealer about a recall for flasher