compustar shock sensor problem

Hey, I have a 94 Toyota Supra with a Compustar system installed. Its the newest 900fm system there is. Originally installed by a shop and I replaces the old system with this unit. My problem is that I noticed that the shock sensor hasn't worked and after looking at it with my multimeter, I've found that the brain (when armed) is sending 12v to the power and ground and 5v to the first and second stage wires. I'm pretty sure there should'nt be 12v going to the ground wire. Do I have a faulty brain or is this the correct operation? Any fix for this?

This is not proper operation.  The sensor will not work without ground on the ground wire.  I am not at all familiar with your alarm system,  Do you know if it has a "ground when armed" wire?   If so have you checked that wire to see if it is working properly?  Have you tried grounding the sensor wire directly to ground to see if the sensor is working?

those systems are awesome!!!!! Compustar makes a great product. This may sound stupid but on the remote control you can turn the shock sensor off. Double check that and email me to let me know what you find. I have seen both the shock sensor and the brains on those go bad although very rare. Im not sure what the wires are supposed to read but I have the same system on my truck and I will check on them for you tommorrow and let you know. btw to turn on or off the shock sensor through the remote hold buttons I and III until the icon appears on the screen. If it is off there will be an icon with a hammer with a ring around it and it will have a slash through the middle. If the shock is on then there will not be that icon.Thank you

Jayson Cook

Columbus Car Audio & Accessories

It's not turned off.

Any further info on this thread? I just installed my first compustar 2w900fm-as (used) and everything worked great except the shock sensor. I used a zip tie to attach it to a large wire harness under the dash, but no matter what I set the sensitivity at there's no response from the alarm. If I physically tap the shock sensor I can see the led turning from green to yellow or red--makes no difference if its armed or not--but no alarm.

Well, the answer to this problem just came to me out of the blue. What a noob mistake! The solution was provided by the alarm going off by itself. Had the shock sensor jacked up full bore and thus it triggered the alarm. I read the older posts about waiting 30 seconds after arming for the shock sensor to set, but unless I time it out my idea of 30 seconds is a lot shorter than Compustars. If I had only waited I would've realized there's NOTHING wrong with my shock sensor. So, for anyone else who's impatient............