Hello everyone,

I have this new problem I can't figure out: whenever I brake hard, the voltage drops (the instrument panel shuts off, lights turn off, doors unlock -- the engine keeps running). Once the voltage comes back up, everything comes back to normal. It's kind of a stinker since it's very useful to have lights on when you're trying to brake hard! If I break only lightly, everything is ok.

Maybe a different issue: a while ago, when I was driving and it was raining hard, the car shut down completely (loss of power)

Any idea how I would go about diagnosing the exact problem and fixing it?

A few weeks before having these issues, I brought my truck to the dealer to fix similar electric issues. They charged me ~500$ but didn't fix anything (they told me I needed to change my driver side door switch and my alternator; However, they are not a big problem IMHO).

I've also noticed there was water leaking under the carpet on the driver side. The water seems to have been coming from the satelite antenna (fixed now -- I believe)
There was also water coming in the trunk: I had tried to install a backup camera but never had a chance to connect it to the lights. The rubber covering the wires between the body of the truck and the door was not installed properly.

-Chevy Suburban 1500 LT, 2013
-4x4
-5.3L, Sunroof.
Installed towing kit.