2002 2500 HD Security & No Start

Ok, last night my freinds, 02 2500HD would start and run for about 2 seconds and then quit, and it would do that over and over again, so we let it sit and tried another key and then it started but the gear selector square wouldnt show up and the truck just didnt run like it should so we undid the battery and let it sit and then reconnected the battery and tried it again and everything seems ok. What were we experienceing? Something with the PassLoc theft system? Cause the security light was flashing when the truck wouldnt start. Any ideas?

The security light flashing and running for a couple seconds and shutting down are definitely Passlock II failures---the system is not seeing the proper resistances in the key tumbler. The PCM shuts down the fuel injectors when this happens- that's why the engine shuts off. Many will suggest you replace or clean the tumbler contacts inside the ignition switch-- a differnt key does not help you becausew the resistor is built into the tumbler- not the key (used to be that way when there was a chip in the key- known as Passkey- but GM trucks never used the Passkey system)- so what I do when this happens is permanently bypass the resistors in the tumbler--I do a lot of remote starter installs- so it is the same thing you have to do then. There is a "box" you can buy for under $10 on Ebay that will handle all this- and you can "dial-in" your resistance value and never have this concern again-- I have done two GM Trucks this way- sure beats the $300+ repair bill-- anyway the only downside is that your theft deterrent is inactive-- but when was the last time you heard someone say-- Thank God my theft deterrent saved me from having my truck stolen!! It always is more of a PITA then a useful feature-- and certainly not a convenience.

What is the name of the box (would you be able to give me a link to an ebay listing) and would you have any detailed instructions on how to install it, or any tips on installing it, we use this truck for hauling a racecar and really dont want to be stuck at the track or stuck in the driveway not being able to get to the track.

http://www.automotiveforums.com/vbulletin/showthread.php?t=336225

Go read that thread. I think it will have some answers for you.

-