Have you checked the fuse or Circuit breaker. Start here before dismantling the switch. If this is o.k. then check the switch. Might be that the shower unit has gone faulty and blown fuse, tripped MCB etc.
Tony T, February 2010
The switch might be broken.
Try replacing the switch.
Adam, February 2010
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I can answer this question...
shower switch light does not come on and shwer not working. What can i do p?