The Whirlpool we put in my parents' place has an indicator light on its control panel that is supposed to indicate under/over voltage, element and control circuit failure. However, it wasn't working too good when the circuit board basically melted... Not sure what happened with that one, took half the circuit breaker with it too.
The whirlpool you are talking about is known to have alot, of problems with their boards,
Bad part you can't even jump them out to get the water heater going to take a hot shower. IMO Whrilpool screwed up on this design. The board cost more than a new water heater
