I took the battery out as I believed it was deffective, and later testing proved that it was not giving the full 12v, but only about 4.5v. I defaulted the system as I didn't know the engineer code, and re-programmed certain parts, months after. We have been experiencing local alarms, which are bell tampers. One of these meant that our custom user code (customer code) didn't work, but the manufacture's default one did. The bell will sound in test mode, but the strobe will not. These alarms are every 1-2 days, and there are two or three of them. Any ideas guys?

Edited August 4, 201411 yr by Gemini

a 2 plus is well old, it could be goosed

There is no way that misprogramming or similar could cause such results, is there? 

if the charger is giving 4.5v no amount of defaulting will help, thats a hardware issue

The battery itself tested whilst not connected gave about that. It was fitted in the 1990's.

batts need to be changed at 5 yrs. if that batt is from the 90s id suggest it as overloaded the charger circuit

I will test both the battery and charger in a few. Could this cause any other faults though, such as the bell tamper?

Personally I'd rip the whole lot off the wall & stamp on it,

If the system was installed properly I'd hang new device on the old wires

If the battery is as old as you say there is no point in testing it, it is in need of replacing. Out of interest how do you propose testing it?

An update of the controls would also be the best cost effective option long term.

Out of interest how do you propose testing it?

shaking ?