Hi all,

Recently i fitted autowatch 446rli with ultrasonic sensor. The sensor causes false alarm quite often. I was wondering if i can adjust the sensitivity of the sensor, if so how?

Also, will closing the Aircond vents help?

Cheers,

the ultra sonic sensor is to detect movement within the car. Most alarms say where the best place for their particular sensor to be mounted. after that, open the windows/sunroof, and arm the car. stick your hand in the window. it should go off soon after you stick your hand in. If its going off before you even pass the window frame, its too sensitive Most sensors have a rotary pot on them - adjusting towards + makes it more sensitive, adjusting to - makes it less sensitive.

these are NOT adjustable.

THESE ARE NOT ADJUSTABLE !?!? Not helpful man. Do you mean these alarms? These sensors? What?

sensors.

what could he possibly be talking about?

if ultrasonic the right word? or are we talking "microwave" sensor?

maybe its the same thing?

they should normally be mounted in the middle of the car, and large metallic objects within close proximity to them can often cause false triggers (things like a pile of coins in the ash tray for example)

They are ultrasonic sensors, mounted on each side of the centre console.

I have checked for rotary pot and found none.

Funny thing is, I disabled the sensors using the remote (as per autowatch's instruction) and 2-3 days later it still gave me false alarm and put car cover on so no wind can go in.

I wonder if there's something else that cause false alarm.

ok, so are these the little sensors that look kinda like hands free mics? If thats the case I dont believe their sensitivity setting can be changed. try disconnecting them physcially from the main unit - if it still goes off, its the main unit. if not, its faulty sensors!

Yes they do. But they are attached to a module to adjust the sensitivity. I've managed to find it and made it less sensitive and still gives me false alarm even when I turned off the sensors.

Because it always goes off 1 day after I lock, turn off the sensors...so the only reason I can think of (a stupid one), because I turn off the sensors for more than one day then the alarm goes off .

Would that be possible???

Disconnect the ultrasonic sensors completely and see if it still false alarms.

If it doesn't, try repositioning the sensors... try putting them at the bottom or the top of the A-pillars.

If it does still false alarm it's a different sensor causing the alarm to trigger.

What kind of car is it in?

It's in 2003 lancer.

Both sensors are located on both sides of the bottom of the central console.

One thing i noticed is that the false alarm only happened after i drove the car. If i just disarm/arm the alarm w/o driving the car, no false alarm.

Last night it went off 3 times (so sleepy today).

Did some further testing and found that it's the tilt sensor that caused the false alarm. I'm not sure whether it's faulty or on the wrong position.

Where's the best place to mount the tilt sensor?