Unfortunately, the Toad alarms are all coded. If you have the code that came with the system, then you'll be able to take it along to any Toad dealer and get them to have a look at it. If you don't have the code, then the main unit will have to be taken out and sent away to Toad for them to reset the code and they'll supply you with a new code.
From what i know, the system usual beeps if there's a fault when it is armed. I had the same sort of problem and it was beeping 5 times when it was armed, then the alarm would activate. After having a look at it, I found out that it was just the bonnet switch which needed replacing.
Try searching the internet for the fitting instuctions for the alarm. Toad won't supply an instruction manual because the system should be fitted by an approved dealer, and they're supposed to know what they're doing. The fitting guide will tell you what the problem could be, depending on how many times the system beeps.
Hope this helps.