Cabin Security Sensor

[is200 Newbie]

I replaced the cabin courtesy lights today which involved removing the light and security sensor unit (all in one)

I have noticed that the USA models have a sunglasses holder in place of the security sensor (the European models have the security sensor instead of the glasses holder)

Why is this? Do the USA ones not have a security system or is this sensor located in a different location?

While I had the unit apart to do the lights I noticed there is ample room to fix the sensor to the chassis of the car and also to have a storage space - in the picture below - I am just wondering why, when its such a simple process to do so, have Lexus not done it? ... there must be a reason..?

Does anyone know if this sensor needs to be installed on its plastic housing (pictured) - will mounting it to the chassis have any effect on the sensitivity of the sensor if that's what it provides? Its only secured by two screws to the plastic housing.

The first picture is of the sensor attached to the housing lid - the second picture shows whats behind the unit after its removed but it doesn't really represent the available space that's available (there is quite a bit) the last picture is of the sensor housing itself showing the possibility of having this as a storage bay if the sensor was located onto the chassis behind the unit which I would expect to be a very easy job as there are enough fixing points and enough length in the wiring.

Pictures below ...

[normski2]

To be honest....not really bothered about the sunglasses holder. I wouldn't want to leave a pair in there on a hot day...they may get buckled with the heat.

Might make secret storage area..admittedly.

[toffee_pie]

secret storage...

[toffee_pie]

I am not bothered at all also, it is weird to leave all that vacant space but not troubled by it.

[ColinBarber]

UK vehicles have an interior sensor so that the alarm system qualifies as a Thatcham Category 1 alarm which improves the insurance rating. It is positioned so that it can properly detect interior movement, pushing it further back and then placing objects in front of it would affect its ability to do that.

[toffee_pie]

Id take that over a stupid sunglass holder.....

[is200 Newbie]

I understand everyone's comments ... I guess the reason for me asking is that the box attached to the plastic door (which is hinged) is a sealed metal unit - a label on the unit states its a 'sensor theft warning unit'.

There is only one wire going into the unit and I am presuming that's the power to operate it - I am guessing its sensing movement from car vibrations in order to set the alarm off as there is no other wire from it leading to other sensors to detect actual movement within the car such as the old Moss sensor ones that were around years ago

[ColinBarber]

It is a microwave/ultrasonic sensor, not a vibration sensor. The signal is able to penetrate the cover. The cable connecting it probably has two or three wires within.

[is200 Newbie]

Thanks Colin

I will leave well alone

[Verbout]

I use this space for my dash cam PCB.

[toffee_pie]

erm, dash cam pcb. I would not put a PCB into that area, Have you heard of EMI interference.

[Verbout]

erm, dash cam pcb. I would not put a PCB into that area, Have you heard of EMI interference.

I have, whats interfering with what?

It's only a 12v to 5v converter the size of a large postage stamp. The car is full of electronics.