Electronic Alarms and Home Security Devices - Problems with Ademco Vista Fault 04

Hi,

I have a ADT Ademco Vista 20p alarm that came the house I bought. I found the directions and reset the code and have been using it for abuot six months. Then yesterday out of the blue it started beeping randomly stating fault 04 1st floor windows. It would be fine one minute and would start beeping the next. So I took a look at it when it was working and I opened every windows It looks like there is a sensor on every Window and the patio door is a part of the same zone. I tried testing every single sensor and had issue with one sensor. I removed it and added it it showed no fault. Then I removed the sensor Ademco 88 (I think, the sticker was kinda faded) for the patio door and put it back together again and it just is constant with a fault 04. Is there a way to reset it?

If you just twist the wires together does the zone clear?

If so, you just need a replacement contact.

There's no magic in the Ademco 88. Just shop for "door/window contact" and buy one that's the same size and shape (no, brand doesn't matter, they are all pretty equivalent)

Ok, tried that. I tinkered with 2 sensors and tried to just take the wires coming out of the wall and twist them together however still no go. I took a closer look at the sensor and I think it a Ademco 988 Intertia crossbar miniature sensor. I have a multimeter and was trying to figure out if there was a way to see if the switch works by measuring ohms nut I got nothing. It was at a constant .2 regardless of the window being closed or open. This loop likes it has 13 windows and the patio door on it. I am not even sure which one is bad. Logically there would be three places which could have problems right? Wiring, Sensors, or the actual alarm? How can I test the sensors individually, is there a way to test the cabling? I would think that the actual alarm system going bad for that zone would probably be unlikely. Please help!

Also I noticed on the patio door there were two wires on each of the top leads and two single wire wires going to the bottom lead. The sensor has a N on the top and a D on the bottom. I would think that the doors are hooked to the bottom by the D and the other four wires would be on the N. Is that right?

It sounds like your windows may have been run jumping from one window to the next, instead of home run back for each opening. This can be a royal pain to trouble shoot as oftimes the continuity break is inside of a wall.

Simple test for the zone input: Take the wires off of the input and put a 2k resistor from terminal to common. If the zone closes, the panel is good.

Remember, the contact will not show closed unless it's in proximity to a magnet.

Thanks for the info. I will need to go to radio shack and get this 2k resistor. But I had a few questions. Question 1: Can the contacts be tested to see if they are operational by using an ohmmeter?
Question 2: I am going to put the resistor in place of the contact correct?
Is there a way to tell if the wiring is in one line or many?

Abrar

You will be putting the resistor directly on the terminals at the system motherboard.

Yes the contacts can be tested with a meter. When in proximity to the magnet, they will show as a closed circuit (short).

(sorry, thought that was fairly obvious)

If you have home run zones, you will see multiple wires connected together (in a series circuit) at the panel head, then connected to the zone input. If you have "daisy chained" contacts, there will only be a single pair of wires on the zone.

Thanks for all the help! I an still struggling with this. How can I figure out which leads on the panel = fault 4? In otherwords the numbers on the panel dont line up with the zones. I removed all the cables from 4 on the panel, and all the keypads were off. So the black and red wires on terminal 4 and 5 on the panel are for power. I would call ADT but since I dont have service with them I dont think they will help.

Again Thanks in advance for all your help.

More Info and more questions...

First the info...
I found that one of the leads has a wire going to it and it says 4. My thought is that that must be for #4. on its on terminal 15 and 16 on the panel.

The Questions....

I bought a 2.2K Ohm resistor pack from Radio Shack can I jump that in place of the wires for number 4?

What should the resistance on the wires be when unplugged from the panel if all is well?

Is there a resistor that I can jump each window with to determine if there is a bad window sensor? It looks like its one cable so its going be next to impossible to check each run. There are a few windows I suspect. So if I can put a resistor on those suspects and if the fault goes away then atleast I have brought the problem domain to a window or two instead of a whole floor. Also I can leave the resistor in place and still use the alarm until I find a new contact.

Please help..... I have made quite a bit of ground thanks to your help!!!

We went through all the windows and the readings are as follows. There seems to be a few suspects but I need to figure out if I can jump the wires and if so do I need a resistor.

Sensor info Window State Open Window State Closed

Patio door 17.49 .3
Dining room 1 omega .3
Dining room 2 omega .0
Kitchen 17.35 .0
Patio door left 16.29 .0
Patio door right 16.38 .0
Rear window 1 16.47 .0
Rear window 2 16.53 .0
Rear window 3 16.67 .0
Side window 1 16.64 .2
Side window 2 16.47 .2
Foyer 1 16.30 .2
Foyer 2 1.56 .4

Please help

Ok, I admire the enthusiasm, but you are over complicating a simple thing.

Hardwired alarm contacts are just simple magnetic switches. When the magnet is in proximity they should read as a closed switch (or pretty close to it); when the magnet is not in proximity, they should read as an open circuit (or pretty high resistance).

The alarm is looking for a normally closed loop with a 2000 ohm resistance in series. Ideally, this resistor goes on the last device in the loop. Because of the way residential systems are installed, in reality, they are usually connected to one of the wires at the zone terminals in the motherboard.

If you do not see al large number of individual 2 conductor wires brought back to the panel head and tied together into a series circuit there, that means that the installer most likely ran a single pair of wires out to the windows and jumped from window to window.

It was commonly done, because it's relatively fast, and uses less wire, but it means that there are usually a lot of wire splices _inside_ of the wall, which can fail, and are very hard to track down and fix.

I'm guessing that you are using an auto ranging ohmmeter and the numbers are simply fairly high resistances. In truth, all you really need to test for with contacts is simple continuity (open or closed).

I suspect that your contacts are good. If you have dummied your zone input closed to verify that the zone input is working, then you most likely have a wire fault somewhere between the openings on that circuit.

Sorry for the overcomplication. I am an IT guy its in my genes :) Nevertheless based on all the info I got from you I really dont need any resistors right? I need to do two tests.

Test 1. Take a small piece of wire, undo zone 4 on the panel and jump the two points where zone 4 connects. If the fault clears its either wiring or the contacts. Right?

Test 2. Use a plain continity tester and test the loop to see if it closes.

It looks like there is a bundle of wires coming into the panel, and there are glass break boxes in the panel as well. It seems like all the wires are bunch up in the panel and only a single pait goes to the panel, and there is a resistor between the cable and panel.

Progress! But more help needed. I went to Fry's and picked up a 2K Ohm resistor and jumped zone 4. Its been clear for about 2 hours. I will leave it for 24 hours and then I think we can conclude the panel is good. Now the next part I noticed that a bunch of wires go into the glass break sensor and two wires come out. It looks like there are two runs, one for the Northside and Rear, the other for the Southside. What is the next step to isolate the issue.

Thanks for all your help!!!!

A picture is worth a thousand words :)

Not sure if you understood the purpose of the resistor so I will explain.

If you were to put a meter on the line to a sensor and it had a 2kohm resistor on the end you would know the line was a closed loop and that it was not shorted or cut.

So based upon that if you put an ohm meter on the loop you want to tests it should show a ~2kohm value if it is OK. If its open then you have a cut wire or disconnected wire. If its closed but has a low impedance then its a short.

So is it an open or closed loop. or is the impedance wrong?

Not sure about the glass sensor issue. I was not able to determine from this thread what the problem was with it.

Re
Sean M



Progress! But more help needed. I went to Fry's and picked up a 2K Ohm resistor and jumped zone 4. Its been clear for about 2 hours. I will leave it for 24 hours and then I think we can conclude the panel is good. Now the next part I noticed that a bunch of wires go into the glass break sensor and two wires come out. It looks like there are two runs, one for the Northside and Rear, the other for the Southside. What is the next step to isolate the issue.

Thanks for all your help!!!!

Thanks for the info, that makes a lot of sense. I made further progress! When I fished the cables out of the panel for zone 4 there were actually three pairs that were in series. I was able to isolate the run which has the fault. I put a simple continuity tester on the three runs and it lit up two out of the three times. So added the two runs that were working back to the panel and am now hobbling on most sensors.

Now the question....

The run that is suspect has a total of four contacts, Three of the contacts have four wires that are going into the wall and 2 more for the magnet. The last one has two wires going into the wall. How should I go abount troubleshooting this run?

Thanks for all your help. I am pretty close to home free :) (I think)

Those are switches. The magnet's the part on the window's moving part.

Start by bridging the contacts closed, one by one (you can just take the wires out of the terminals and twist them together)

what you actually have at the ones with multiple wires is an incoming pair and an outgoing pair. The magnetic contact breaks one side and the other just passes through.

If the contacts are all good, the next thing you can do is to bridge segment by segment to isolate where the break is.

This is one of those things that's a lot easier to do than it is to describe.