Your problem would be best solved "changing the pull cord switch ". DONT try if you are not sure, or fully competent.
Make sure the power to the particular shower circuit is off - if attempting DIY.
(You should possess some testing "neon tester" , & appropriate screwdrivers, etc, also 1st checked if this unit is an its appropriate fuse at the consumer unit - and fuse not tripped ?? ) - If in doubt consult an electrician/ or a competent diy relative ???
H. Chung
October 2005