Shock Sensor going crazy

I think my shock sensor is going crazy. Since yesterday evening and five times last night, my car alarm has been going off randomly. I thought it was some tiny fruits falling from the trees above or the rain drops. I sat in my backyard and suddenly heard the alarm go off again. This time I witnessed nothing hit the car, not even the rain. Therefore I decided to dissect the alarm electronics and do a physical inspection. I noticed that the shock sensor seems to be too sensitive. Zone 1 and Zone 2 are both very sensitive so I played around with the two pots, full anticlockwise and adjusting one at a time very slowly. Most of the time both zones get fired off even with minimal sensitivity.

My alarm system is the Omega Max.

As per any of you pros out there, what shock sensor is the best performer? I would like to buy a dual zone shock sensor and replace my sensors.

The first step is to troubleshoot to verify that's what's causing the false alarm.

Most alarms have some sort of notification system to tell you what caused the alarm to go off..........door, trunk, hood, shock, etcetera.

Usually this is done by counting how many times the LED is flashing, before you turn the ignition on, but every brand is a little different.

What kind of car do you have? There are a few cars where the door trigger, if wired improperly, can false after a while.

I found which shock sensor was the culprit (I have two shock sensors, one wrapped around the the steering column and one behind the glove box very tightly held in position to a metal part of the frame. Reason why I have two is as follows: The one on the steering column works for very hard knocks, but not for the pre-warn siren. Therefore I got myself another one from Omega, which worked very well till few days ago. Now even the prewarn is making the full alarm go off. For now I disconnected that one and the problem has gone, however I dont have a prewarn sensor.    

I really would like to know which shock sensor is really good quality. I want to buy one and need a name/brand of something that has a good track record. I don't mind spending more for a good quality sensor.

I would probably recommend a DEI shock sensor off ebay. Should be like $5

Question... Did you diode isolate the sensors so that there would be no feedback?
If not thats most likely your problem...
For an example of how to do this visit the link below...

https://bulldogsecurity.com/bdnew/newsite/pictures/instdiagrams/121.jpg

-Kitt

Yes, I have diode isolators between each sensor and also between all 4 door switches, which I remember soldering with quite some pain as it was very difficult to reach the connector. As I've disconnected my siren (to not bother my neighbours) and disconnected the right shock sensor, I haven't had an incidence in the last few days. I would know if the alarm goes off without the siren because I have an Ecco 2 way transmitter which beeps when the car alarm goes off.

unplug the shock and seeif the prob goes away

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I can eat fifty eggs

Check the manual that cmae with the sensor and see if you have to disconect a wire when setting it sensitivity... I had a problem with that on an omega sensor once.... Also do I diode check on the diodes an make sure that there ok...
If all else fails I think you shold try a new sensor.. Also make sure the sensors are not mounted down so they cant move this can cause problems for shock sensors.

-KITT

I disconnected the sensor and the problem went away.

ALso I will check the diodes this Saturday to make sure they did not short or cut. I did not know the position of the sensor mattered. I have both my sensors vertical. Could that be a problem? And no, both my sensors are Omega sensors that have 4 wires and 2 controls. A +, a-, trigge1 and trigger2.

Now do I have to mount the sensors horizontally?

Mounting the sensors verticaly fine... what I usually do is lighhtly ziptie them to a wire harness in the vehicle... just make sure that the sensor could move....

-KITT

By any chance is the problem sensor mounted close to the transmitter antenna? Possibly the transmission from the prewarn is triggering the sensor and sending it into full alarm, as they tend to be sensitive to RFI.

glantern83 wrote:

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Mounting the sensors verticaly fine... what I usually do is lighhtly ziptie them to a wire harness in the vehicle... just make sure that the sensor could move....

-KITT

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I did tie all mysensors with two zipties, very tightly but not to a wire harness. I tied them to a metal part of the frame. Is that not the way? I thought the sensor was not supposed to move. I thought shock sensors were supposed to 'feel' anything happening to the vehicle and the best place was the metal frame. Correct me if I am wrong.

They are quite close, but not too close. There is about 12 inches distance between the antenna and sensors.

Also this whole thing worked perfectly for more than a year just the way it is. Suddenly, this problem sprang up and manifested continuously almost every hour or so. I am convinced it is a bad sensor and purchased a DEI 504D sensor, but i see only 1 pot to control the sensitivity of both zones. I am not sure how I can control the two zones with one control. Can someone help me with this? Thanks.

With DEI they tell you not to ziptie them tightly just zip them to a wire harness... if there ziptide to tight it xcausers problems... as for being to close to the antenna I really dont know if that would cause much of a problem... The antenna is shielded....

-KITT

plug it back in and turn the controls counterclockwise all the way down. plug it back in and see what happens.

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I can eat fifty eggs

gregory863 wrote:

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plug it back in and turn the controls counterclockwise all the way down. plug it back in and see what happens.

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I've already done that and it wasnt triggering anymore. Even a 1 degree clockwise turn of the full sensor causes it to be fire off when the prewarn fires off.   So I concluded that the sensor is bad and purchased this DEI sensor, however what I need now is just to know if/how I can control the two zones with just one screw to adjust.   The box came without any papers inside explaining how to use one pot to adjust both zones. If someone could help me with that, it would be great. Thanks as always.