proximity sensor

A week or so ago I installed a prox. sensor for a really nice customer. He originally had the alarm installed and even though the shock sensor was securely fastened to a metal brace under the dash, he was having issues with kids actually climbing onto his van. They have broken his mirrors, dented his hood, and broke his visor. I actually feel bad for him because he is stuck in a wheelchair, but he is one of the most pleasant person I have met. So I told him about the prox sensors and he ended up picking one up off ebay initially (got it for 1/2 the price we sell it for, and in a lot quicker time). I put it in, and finally got it programmed perfectly. I tested it both in the bay, as well as in the back of the parking lot where there would not be any interference. It worked beautifully (which is surprising because we all know how much of a pain they can be). However he came back in about 3 days later saying that it worked fine for a couple days, then the outer field just disappeared. He brought it in and I checked it all out, but could not find anything wrong (besides the fact that it wasnt working). I ran a whole new power straight from the ignition, a new ground straight to the metal frame, and new activations which were both diode isolated to prevent feedback from shock sensor. Well I explained to him that it had to be the sensor, so he decided to go ahead and order one from us. Well it came in and I put it in and once again it was working beautifully. Well he came in the other day and its the same problem as the old one. I set him up with an appointment for Saturday I believe, and really would like to get this fixed. It is an 05 Chevy express van with the sensor mounted up near the firewall above the center engine "cover". He only wanted it for the front end, so I mounted it as far forward as possible. Sorry for the long post, but I wanted to get as much info in as possible. All answers would be great. KennyKenny

Owner / Technician

KKD Garage LLC

Albany, NY 12205

PS I also installed one in a Mercedes (Dodge) Sprinter in front of roof lining. It worked best when I mounted it sideways.