henkinc

Checking the cause of my alarm randomly going off in my 1997 cab, the dealer saw a history of the interior monitor as the cause. I take out the #29 fuse for the interior light (which houses the interior monitor in some fashion) and got two days with no alarm, so this diagnosis seems correct. I put the fuse back and I get only three hours without the alarm going off. These last tests are with the top down.
Has anyone else seen this problem? Could the monitor perhaps be dirty and is there some simple way to clean it - like a cell phone cleaner? Comments?
Charlie

vincer77

What is the interior monitor?

aj986s

The interior monitor is on many Cabs, including the Boxster (have it our 2000 Boxster). Its basically a motion sensor, so that if someone tries to enter the car by cutting through the fabric top, it will set off the alarm. But IIRC, it only works with the top up. With the top down, bugs/critters/leaves fluttering in the sensor's view can set it off. For our 986 Boxster, there's actually a "Red Clip" available that fools the system into thinking the top is actually closed, so that the sensor still works while the top is down.

http://boxster.wikia.com/wiki/The_Red_Clip


Maybe the top up switch is stuck, and always thinks the top is closed, making it more susceptible to bugs/critters/leaves fluttering in the sensor's view.

henkinc

in my case - the 993 cab - the alarm has gone off with car in the garage at night with no activity around and with top down, so allegedly the monitor system is turned off automatically.
On the 993, the monitor can be TURNED OFF I learned (read the manual) in case one wants to leave a dog in the locked car, for example. But this implicitly is relevant only when the top is up. Anyway, I tried turning the monitor off and will see if the alarm again goes off on me at some point.

question for 993 guys - if you turn this sensor off (just hold the light itself in for a few seconds until it blinks 3 times), does IT STAY OFF?? I doubt it. It must go back un whenever you lock the car again in the future. Correct?

aj986s

If the alarm is supposed to be off with the top down, then possible the switch that tells the system whether top is up or down may be stuck in the "up" position, fooling the system. Consequently, even with the top down, a flying bug/moth/mouse/etc. in the cabin area could set it off.