[f5fstop]

The module that controls the ignition is called the BCM. The BCM also controls the lights, the washers, and about everything else.
First Hummer asked if you had marker lamps...do you?
The BCM is in a pretty water tight area, and unless there is some leakage somewhere else, like mis-installed marker lamps, it should stay dry.
Most important thing is if there is a water leak, tell the dealer not to just replace the BCM, but to locate and repair the water leak. If not, you will be back again.
The H3 is designed to be as water tight as possible. If you don't have marker lamps, there could be a problem; as any man-made object can have.
Important thing is to get the dealer to fix the water leak...that is if it was really due to a water leak. Possibly, the dealer can't tell and just automatically blamed it on water.
Some dealers believe they have to blame it on something, rather than admit that it was due to something they can't explain. A BCM can go bad on its own, not a real problem, but again, man-made.

I have gone through deeper water, at a faster speed, and no problems here.