20P and 6160 issues

[daltex]

I have a Vista 20P with three 6160's that are driving me nuts. I spent many many days configuring and programing this system with an expansion board for alot of zones. Each zone has the name of the area appear on the keypads, X10 light control etc. The system is maybe 10 years old give or take.

For the last few years one of the keypads has been erratic in that it would show zone faults, armed/disarmed mode etc. but the pressing of buttons would immediately turn the led's into boxes and it would beep as if inputting incorrect codes.

Having recently installed VOIP I recently had to check the ability of the Nextalarm modem for proper communication with the dispatch center. Putting the system into armed mode and opening a door set off the alarm and the alarm co was properly notified. All was good until I attempted to shut off the alarm and reset it. Nothing happened the first few tries then it went into a keypads beeping mode. Attempted from other good pad and still nothing. Attempted from bad pad and nothing.

This had happened before and I had  reset it (pull AC and battery). Since our alarm is only triggered once a year at most it just didn't cross my mind again until this last episode.

If it's only a keypad replacement or two then I'm a happy guy but if I lose all my programing by replacing the main board then I'm crying big time. 

Any thoughts on diagnosis? Thanks in advance.

[DEL Installations]

Could be a keypad going south.

Have you tried swapping or removing that keypad from the system to see if the conditions continue?

Also, when was the last time the system's battery been replaced?

I'd be slightly concerned regarding the amount of aux power that is available, since you mention 3 alpha keypads and multiple expansion in addition to protective devices.

[SmithWesson]

That's what it sounds like to me.
I would definately try an auxiliary power supply for the additional key pads.
Try this,
disconnect all keypads except the "bad one".
If it works properly than you most likely have a power issue. If it still gives you trouble disconnect the bad and hook up the good. If it works this way then it's probably the keypad.

My bet is on the power issue

[Airdorn]

The older 6160's had a flaw, where the circuit board could be 'pushed' away from another pcb inside of it, over time from normal keypresses. It seems the force people use to push the buttons was enough to gradually cause the problem.

If you take the keypad off its backing, you might notice the main pcb slightly pushed away from the LCD pcb.

The simple fix is to squirt a bit of silicone sealant between the two and then push it back together tight. Give it time to cure and you're set.

They've since redesigned the 6160 to use a ribbon connector to the LCD.