it depends on how old the alarm is, type in the code then press oo then 01 then the new code then prog then reset .if this does not work try ,type in the code then prog then 60 then new code then prog then reset ,hope this helps
brad
September 2008
Enter existing code
Press Prog
Press 60
Enter New Code
Press Prog
Press Reset
acorn
September 2008
Automatic Answer
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