Weeks ago, the trouble light was on. I pressed *2 and saw zone 1 was on, which means low battery.

I bought a same model battery from RadioShack (12V, 5Ah). After I replaced the battery, the trouble light went out.

Then I wanted to reset the panel since it's opened (coz I never knew the master code). I power off AC and battery, shorted the RESET EPROM pin, power on. Master code was reset to 1234. I can program each function without any problem.

But the problem is: the trouble light came back! It's zone 1 (low battery). I used multimeter to test the battery and the fuse. They all good.

I unpluged the AC while the battery was connected, I heard siren, which means the system was getting power from the battery (otherwise, there would be no siren).

I also read from the forum, it might be the system clock. I program the system clock with *6+master code+1+4digit time. The trouble light still won't go away. It's always zone 1 (low battery).

I thought about the possibility that the main board was broken. But it's unlikely, since every feature seems good. Except for the trouble light is on.

I can live with it. But I'm really curious what would cause the trouble light 1 on.

Thanks!
Michael

 

Check the fuses on the upper left of the board. It's possible that you popped the battery fuse while you were working on the panel.

 

If the fuse was in bad contact(or open), would the siren sound when you disconnect the AC?

 

Siren and battery are 2 diffrent fuses. Check the fuse as ron said. But also use a volt meter and make sure that the battery leads have 13.5 volts on them without the battery connected. The panel may not be charging the battery properly

 

Um... Did a test with the battery removed. The lead is giving 13.78v. Does that mean the fuse is good?

 

Ok, also check the voltage with the battery connected. There should be at least 12.5 volts at the battery terminals. If so, then it's not impossible that the battery detection portion of the charger circuit has died on you. No fix for that, except for a MB replacement.