like with any car - it's safer to stay out of floodwaters. too easy for the car to be swept away, and you don't know what's lurking under the water that might come up and bite your car...
it's not really the HV cables that you have to worry about, its soaking the ECUs that are at floorboard level that isn't good. (Besides setting yourself up for a forever moldy car...)
There was some dramatic flood video that was shown internationally a year or two ago, which showed a helicopter rescue of a woman from her white Classic Prius that was being swept away by flood waters. So, electrocution is not a problem (what most people ask about...)
The intersection next to where I work is prone to flooding whenever the rain is heavy enough, and even more so if the drains are clogged with leafy matter... It's a fun sport for us to go watch all the cars getting stuck in the water, as opposed to turning around and using the other nearby exit from the office park... Quite fun watching the idiotic tow truck people dragging the car through the deeper portion of the flooded corner, then dropping the car, and then opening the door to get into it again to try again... <evil grin> anyhow, after the "lake" as we call it subsides, it's amazing the stuff that is in there: besides the sharp curb that was hidden and has taken out many a tire/wheel/hubcap, there are upturned hubcaps with their sharp edges looking for tires, and I've even seen a 2x4 in there with a few rusty nails pointed up, too. They were all hidden under the flood waters, so if you had ventured in, you wouldn't have seen them and likely would've driven over them...
