Hacking GM's BCM

[fluoronator]

I'd like to add a security alarm to my '09 Chevy Silverado. I'd like for the alarm to flash the headlights and pulse the horn. Can the lights and horn be accessed via the BCM? Could anyone point me to any good information on the pinout and examples of accessing the module?

[haklesup]

First you'de need a CAN bus tool. The most flexible readers are interface cables to a laptop. With this system, you at least have a chance to figure out the signals to make things happen.

However, most alarms do not flash the lights and honk the horn via the cars internal bus, they just piggyback some relays to the light and horn switches and control those relays directly. That's a hell of a lot easier.

YOu should get a good wiring diagram for your car. Usually can find it on Ebay or amazon