Hello Roger, my name is George,
The cause could be one of a few things:
Regarding a fix... Firstly we would need to determine what of the above has taken place and then rectify that by replacing the respective part, or you could opt to replace the complete dispenser.
Importance... The dispenser is used to dispatch the detergent at the correct time.. This is usually about 10mins into the cycle..
It is possible, as you have suggested, to place the tablet on a saucer near to where the tablet would normally lie once dispensed.
The actuator arm is at the rear of the dispenser inside the door.. To get at it you would need to dismantle the door.
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