Inside the appliance on the rear is a small pump,
this pump pumps the water up to the water container, via small bore pipe.
sometimes this pump fails or the pipe gets clogged with debris,.
Another thing to check is the device that sends the signel to the pcb, which inturn illuminates the water LED.
This device is basically a float operated micro switch,sometimes either the float sticks or the switch fails.
The wiring for these components must also be checked for continuity,and also the security of the connectors,.
If all checks out ok,then its most likely the pcb has failed,
but to make certain you should also check/meter the heating circuit.
Meter the heating element and the three thermostats,and check the wiring.
Hotpoint usually have a five year warranty on selected dryers,so do check your warranty status,
the appliance will need to be checked thoroughly before the pcb is suspected as a failure,.
You are going to need a multimeter,
if you decide to investigate and attempt a repair,then post back on here if you run into any probs.
paul
March 2012