Electronic Alarms and Home Security Devices - Armed LED on DSC LCD5500Z will not light up

Hello all!

This is my first post but I have been reading over this forum and have gathered all kinds of valuable information on my DSC 5010 (Power 832) system.

I have run into two little snags however. I just replaced a 5508 LED keypad with a LCD5500Z. I powered the system down, swapped them out, powered back up, assigned the keypad a slot, ran the supervision, and reset the system clock. Everything is working great so far but here are my problems:

1. Armed LED will not light up in either Stay or Away modes even though the LCD display says the system is armed (and the Armed LED is lit on second keypad in the master B/R).

2. When Stay arming the LCD display shows that the keypad is waiting on the exit delay. On the old LED keypad (and on the second one) stay arming was/is instant.

As far as #1 goes, I have determined that the 5500Z is v2.1 or older and uses the two digit section numbers. I did check that [61] 2,3 and 4 (Stay, Quick, and Interior Arm prompts) are all on, but I don't know if they apply. Is there a way to test the LED? I have not put a meter to the LED legs when armed to see if it is simply a bad LED but I can if needed.

I'm sure if I dig through the install and program manuals I'll find a fix to #2, but so far I have not found it. As everyone has said, the DSC manuals are not the easiest to read.

Thanks in advance for any help and sorry for the lengthy post!

Tank

Actually, the exit delay time _always_ times out, whether in stay or away modes. It's just that with the LED keypad, the _audible_ count down turns off in stay mode, but the actual delay count down still runs. Even if you trigger instant mode, the delay has to run out before the system actually arms. With the 5500z keypad, it shows that the delay is running, even with the audible suppressed.

This is an anti-false alarm feature that nearly all alarm systems use (I think it's a UL or CP-01 feature)

The LED not lighting, is just a bad LED, there is no programming command to turn that on or off.

Thanks for the information MrRon.

I did finally find out that during a system test all of the LEDs are supposed to flash. I ran the test and only the Ready and Trouble LEDs lit up so you are absolutely correct that it is probably a bad LED. That would also explain why it does not light up when stay arming. I am assuming that if it were lighting up properly then it would illuminate while the LCD is showing to delay countdown. I just never realized that the LED keypads had a stay delay countdown since the armed light would illuminate immediately and, as you said, the audible countdown tones were muted in stay arming.

Thank you very much for taking the time to respond to me, as well as everyone else you have helped here.

Now off to the solider bench to replace a LED.

I hope everyone has a GREAT weekend!

Tank

It's one of those things that they mention in passing in one or two places in the user manual, so most people really don't catch it.

Especially DSC panels, which default to a _2 minute_ exit delay initially, often confuse people when they are testing systems, because they will arm the system in stay mode, run over and open a door or window and be puzzled that the thing didn't go into alarm.

Hi MrRon,

Here is what I have discovered. I checked the voltage on the Ready LED when lit and found it to be right at 1.95vdc. I then armed the system and tested the Armed LED and found zero volts. Now I was scratching my head because even a bad LED would show voltage on the board. I got to looking and found that there is a tiny (probably 2mm x 4mm) flat rectangle black chip that is missing in the Armed circuit. They are present in the Ready and the Trouble circuits. They are marked 195. I think they are 195ohm resistors but I'm not sure. I can't tell if it was missed in manufacturing the board or if someone removed it.

I can probably find one on a discarded piece of computer equipment around here, but if not do you know where I can buy one and what is it called?

Thanks again for your assistance!

Tank

I have no idea.

These days, in this era of surface mount components and conductive cement assembly, I don't do field repairs of things like keypads anymore. Half the time, even if you can spot the bad component, getting the replacement to integrate into the circuit is hit or miss.

If you bought this keypad from an online vendor of some sort, I'd be more inclined to request an exchange.

I looked a little closer at the resistor and see that it actually has 561 printed on it rather than 195, I was looking at it upside down. It's amazing what a little more light and a magnifying glass will do. Which would mean, I think, that it is a 560 ohm resistor.

I picked this up for cheap, so it would not be worth returning it. I'll get to digging around in my scrap pile and see what I can find.

Well, I fixed it. As I had said earlier, there was a space on the board where it appeared a resistor was missing. I added a 561 resistor to the board and now the Armed LED lights up as it should.

Thanks for the update. You are persistent (in a good way). As I said before, I don't do field component replacement, anymore, as it's too much of a crap-shoot.