Charging system failure

The loss of power steering assist along with the charging system failure points to the belt was slipping due to being severely overloaded with water. That is why everything is working normally now and during the charging system tests. Having the charging system tested is the right thing to do, but if the failure is intermittent, that testing must be done while the problem is occurring.

Be aware that way too many people think when power steering is lost, they cannot steer the car. A lot of people just sit and watch as the car goes into the ditch. The fact is both steering and brakes never lock up or disappear when there is a failure or the engine stalls. On GM cars in particular, it can take two men and a boy to push the brake pedal when the engine has stalled, but it can be pushed. The slower the car coasts to a stop, the harder the steering will be, but the wheel can be turned.

You listed "heavy rain" which is not a common driving condition. If you drove through standing water, it can be expected that water will splash onto the belt and cause slipping. That can happen to any car and the problem will go away very quickly. The same thing can happen to the brakes if the rotors get flooded with water. You can lose the brakes completely, but disc brakes have a huge advantage over the older drum brakes in that the pads squeegee the water off, then braking power returns very quickly.

If this is all that happens, and only when it is raining hard or you blast through a puddle, there is no repair required. Just being aware that power steering will return is enough to keep us from panicking.