Alarm Sensors
#1
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Hi All
My factory alarm/demobilizer has recently started being triggered for no apparent reason after being armed. It appears that vibration such as windy conditions sets it off and as far as I know there are no motion sensors in the car?
Your responses are appreciated
Bill
90C2
My factory alarm/demobilizer has recently started being triggered for no apparent reason after being armed. It appears that vibration such as windy conditions sets it off and as far as I know there are no motion sensors in the car?
Your responses are appreciated
Bill
90C2
#2
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Bill,
I have had this problem in a BMW when I've left the dashboard air vents open - as the wind blew, it disturbed the air inside the car enough to upset the ultrasonic detector - strange but true!
Barry
I have had this problem in a BMW when I've left the dashboard air vents open - as the wind blew, it disturbed the air inside the car enough to upset the ultrasonic detector - strange but true!
Barry
#3
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Hi Barry
I don't think I have an ultrasonic detector in a factory installed alarm/demobilizer - do I? I thought the only sensors that existed in this system was the door switches as well as the switches for the trunk and engine lid?
Bill
90C2
I don't think I have an ultrasonic detector in a factory installed alarm/demobilizer - do I? I thought the only sensors that existed in this system was the door switches as well as the switches for the trunk and engine lid?
Bill
90C2
#5
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Bill,
I think it depends on where you are in the world - my C4 has ultrasonics on the rear parcel shelf. In the UK the alarm was upgraded when the car was new to meet Insurance requirements - caried out, I believe, by a firm called Hamilton and Palmer on behalf of Porsche. I'm sure I'll be corrected by those with better memories. It must have been a good quality install as it still works 15 years on!
Barry
I think it depends on where you are in the world - my C4 has ultrasonics on the rear parcel shelf. In the UK the alarm was upgraded when the car was new to meet Insurance requirements - caried out, I believe, by a firm called Hamilton and Palmer on behalf of Porsche. I'm sure I'll be corrected by those with better memories. It must have been a good quality install as it still works 15 years on!
Barry
#6
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Glove box switch is the most likely cause.
Porsche never installed anything but a basic alarm at the factory. Certainly I can assure you there are no motion sensors installed. The 1990 C2 has the old 928 analogue style alarm system. Just switch inputs open when not activate and grounded when activated.
Mobile phone cables in glove compartment?
Ciao,
Adrian.
Porsche never installed anything but a basic alarm at the factory. Certainly I can assure you there are no motion sensors installed. The 1990 C2 has the old 928 analogue style alarm system. Just switch inputs open when not activate and grounded when activated.
Mobile phone cables in glove compartment?
Ciao,
Adrian.