dual zone proximity sensor

That one, I was struggling to think of the correct name, is there one available suitable for alarms that works well? Thanks

Look around the page I quoted, they all work well if correctly installed.

508D is one of my favorite topics. Listen to Howie on concentrating on having protection in the driving area. If you are worried about the back hatch, put in a truck pin that will activate if someone pops open the back. The dual zones of the proximity sensor will be blocked by any metal they have to penetrate. Also keep in mind the zones take a few seconds to set before they will be active. this may be why you get a full trigger one time and not another. Temperature also makes zones more sensitive when cold out, and less sensitive when hot. It was noted by someone who has a DEI certification that the zones don't fully set for 20 minutes after arming alarm. Not mentioned in the manual. Not sure of the accuracy of this but might be accurate in your case

Birdman41; Clifford used to be trunk, hood instant, doors 15 seconds and prox/mux 25 seconds. Also after 3 inner zone triggers the 508d will TURN OFF, has to be reset by turning ignition on and off. 508d itself won't actuate for 4 seconds. Your comments on position echo why I always try to go for the roof lining where possible.