motion sensor wiring 2 wires

Make: Ford Model: Ranger Year: 2004 Alarm: Visteon (original Ford install) I have a motion sensor on my dash with two wires. The sensor does not activate the alarm. One of the wires are grounded (screwed into the bodywork in the footwell), whilst the other wire is dangling loose (no copper visible outside of the sheath, as if the wire was cut clean-off). What should this second wire be connected to? Can I crimp onto the internal door light switch (which also sets off the alarm)?

To add to the above, the Burglar Alarm Unit has the following written on it: BL2A 67 791 2K21A Naldec 34111 42 (I believe that Naldec are now a part of Visteon?)

Yes but trunk trigger is a better option via an inline (1N4004) diode, band towards the join. I also very much doubt if it's a motion sensor with two wires, more likely to be a simple tilt sensor.

I also suggest you contact Ford customer service or Google the info. I just don't think it's any sort of sensor with just two wires. Also beware on a US site, the US ranger is a Ford and completely different from our Mazda made model.

Thanks for the reply howie II. Below is a picture of the sensor in question. Is this not a motion sensor? For customer service is absolutely useless so no help there :(.

Some more information: The door light switches (which activate the alarm) are usually NO, the alarm activates at NC. But each switch has a ground and positive... I tried the following: 1. Connecting both wires together to the ground (i.e. screwed to the chassis). This didn't do anything. 2. Connecting one wire to the ground, and the other to the door light switch. The green LED on the sensor lit up, however when I made a noise or moved around, the alarm didn't activate. 3. As above, but changed the wires around. This didn't do anything.

It simply means that the switches themselves aren't grounded, that "12V+" is the switched ground return for the courtesy (dome) lights. That's the only wire to connect to but I don't believe it's a sensor if so it would have had at least three wires, ground (earth), power and trigger or 2 trigger wires for inner and outer zones and it's probably a shock or tilt sensor definitely NOT a prox the alarm wasn't sophisticated enough. You're barking up the wrong tree time to bin it.

It could even be half of an ultrasonic detector with two wires the other half is missing!

I would much prefer a shock sensor, and it could be one with just 2 wires, yes? I have an Electrical Wiring Diagram for my vehicle, however it doesn't make any reference to such a sensor, or at least I cannot see a reference!

Not available with two wires you're obviously not reading or taking in previous posts.