Car Alarms: Subaru Sigma M30 Alarm going off, sigma m30 alarm, external sensor

Question
Hi.
i have a classic scooby with a Sigma M30 Alarm fitted. Unfortunately, it has been going off randomly for no apparent reason, there is nothing that is dangling or that will move and it has even done it in the middle of the night, then after turning the alarm off and rearming it. I sat at the window and watched it to see if anyone was messing with my car, it still went off with absolutely no-one anywhere near it.

It's only just started doing it, could it be the sensors are too high or the heat?

Thanks Lou

Answer
Sure it could be the sensors, if you have a temp sensor.
but there's more to this them meets the eye...

If you have a power issue in the car that "spikes" the
Sigma monitoring circuit, this too could set
it off, as these alarms detect perceptible batt. drain
and report it by triggering the siren.

Please have the alternator and charging system inspected
to be certain it's in top shape, and let me know
if this corrects it. If not, you
may have to pull the sigma's external sensor pack
to test to see if it's gone loopy (technical term -LOL)

Keep in touch.

ALARMTEK