Any ideas on this one?

When I step on the brake pedal, the left turn signal blinks fast (like a bulb is burned out). When I step on the brake pedal with the right turn signal on, it blinks at the normal speed.

Thanks in advance

 

Sounds like you have a ground problem with your left brake light and it's feeding through the left turn signal.

 

I have the EXACT same problem, but since it is winter I just have not addressed it yet.
It is the turn signal bulb holder in the rear bumper, it does not have a good connection and the extra drain of the brake lights on the voltage makes the turn bulb loose power.
Have a friend turn on the left turn adn hold his foot on the brake while you push the connector into the bumper turn signal, it will blink normal until you let go.
I have just stopped using my left turn signal until spring.

 

That's fine just go around the block enough time to make all rights until spring. It will be like $1,000 in gas, but at least you won't get cold!