Factory Theft detterent system, how effective is it?

[HHummer]

The H2 has never had the PASS-key system. It has the PASSlock theft deterrent system which is a little different. Here is the GM description:
Anti-Theft Systems

PASS-key theft-deterrent system
To reduce the risk of car theft, many GM vehicles feature the patented PASS-key theft-deterrent system. Each ignition key has a black, coded resistor pellet embedded in the key. When you put the key in the ignition and turn it, the system reads the resistor. If the system doesn't get the correct code, the car won't start.

PASSlock theft-deterrent system
Similar to PASS-key is the PASSlock theft-deterrent system. With PASSlock, when you turn the ignition lock, a sensor in the lock sends a resistance code to the on-board computer. If the code isn't correct, the computer shuts off the fuel to the vehicle's engine. PASSlock doesn't require a coded resistor pellet in the key.

Both systems have been incredibly successful in limiting theft of GM vehicles. In fact in 1984, before this system was developed, the National Highway Traffic Safety Administration reported that 13 of the top 20 stolen cars were GM models. By 1995, no GM vehicles were on the top 20 list.

The H2 does not require the special resistor key as previously mentioned on this thread. So, if an impression or copy of your key is made, it will work identically to the original. Breaking glass has no effect, but then opening the door will set the system off. I believe that the second post is correct. If the door handle surround is compromised and the key lock is operated internally it is the same as a key. Of course, the ignition would still be a problem without a key. And, in theory, if the alarm is initiated, Onstar will come online and ask for your pass code, assuming you have your basic package subscribed.

One very effective addition is a simple hidden switch installed into the ignition wiring. It can be located in some obscure location known to you. Anyone breaking in would normally not have the time to diagnose the electrical ignition system to find the open. It also has the advantage of being an unknown unlike a canned system.