Induction hob keeps bleeping and not 'swiching on'?

-goes on for hours-occasionally it will stop and I can then use it-but not all of the 'rings' are working.It is a Hotpoint and about 5 years old.Help!-it is driving me mad-and it is on the same wiring as the cooker so I can't switch it off at the mains when I am using the cooker which I have to use as cannot use the induction hob!!Any suggestions be very very welcome.I have called a couple of appliance engineers but they did not call me back!Am desperate now-my son handy with a soldering iron if we can fix it ourselves-I rang Maplins with make model etc and got a very indifferent man telling me to call an engineer ...am at wits end now..