Hi Jon,
Sorry, if you need a faster reply simply send an e-mail, I don't check this site as often as I should.
The alarm that apparently caused problems was not installed by me personally, although I'm handy
with these things I didn't want to take chances. Instead I had the most reputable alarm installer in Toronto do the work...the place is always busy with European exotics such as Maserati's, Lamborghini's & Ferrari's...so I felt safe. They were pricy but they assured me that they know their stuff & are familiar with Mercedes electronics.
After the Sprinter's electronic problems were fixed I still wanted an alarm but Chrysler & the alarm installer refused to move an inch & not take any further risks. I convinced the alarm installer to replace the Viper with a basic $50. Audiovox. Only 2 sensors are now connected to it, without disturbing any of the Sprinter's electronics. There's a shock sensor and an air pressure sensor. The air pressure sensor (which they told me is recommended for all large vans & trucks since entry is easy thru large windows) is better than I expected, it actually works. It did need a few sensitivity adjustments but i've been happy with the system for almost 1 1/2 years. I added a louder automotive horn which beeps along with the alarm's siren.
Hope this helps,
Josh