are you putting them in the right way round? un do small screw and look for moisture inside, dry if need be, make sure tiny on/off switch is going to off position, clear any dirt/dust,i had similar fault, too dear for new key for me, so i took out master alarm switch key its under bonnet in front of passenger side top right corner above brake fluid reservoir round hole just twist it out,now you have no alarm to set,just lock up with key and open with key,no alarm to worry about or batteries. have ago, easy peasy,good luck.
scouse ronnie
November 2010
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