GM Truck Club Forum banner

Aftermarket Alarm causing system lockout?

4935 Views 4 Replies 4 Participants Last post by  unplugged
Hi, All....I'm a newbie here to this site, so I hope that I am posting in the correct area. Anyway, I have an '05 Z85. I've had it just over a year now and had a aftermarket alarm/remote start kit installed a few months after getting the truck. As of late, this morning being about the 6th time, the I go to start the truck and it would not start! Now, basically, the anti theft that's built into the truck kicks in and I have to wait for the system to restart/clear itself which takes about 5-10 minutes and then the truck will startup! I brought it to the dealership about a weak ago and they said all the electrical systems check out fine, etc. and there were no problems found. Now this morning, I brought the truck back to the dealership again and they say this " Aftermarket alarm wired into VATS system causing security codes. The voltage difference will cause vehicle to go into theft mode and have to wait 10 minutes to reset itself. Now of course the strange thing is that, when I had the truck in to service last week, they said all checks out fine and that they could not duplicate the problem. Now a week later, all of a sudden, there are security codes, etc.!?

I'm wondering if anyone else has had this issue! I have a Python system installed. It's from the same company that makes the Viper alarm system.

Also, I should note that I also have a GMRC1 installed in the dash so I can use my own aftermarket radio. Could the GMRC1 be causing the problem?

Thanks for any help!
1 - 5 of 5 Posts
well welcome to this site ........
Trust me yes i have the same problem dealer said everything is fine but when i try to start the colorado my battery is dead.....since the wiring is very diffrent to other trucks since the colorado is anew line of truck..... the negitive is reversed on this truck dont knoww how to explain it very well in word i to say i am waiting for the OEM Cd Disk from GM....... to find out how the system run and fine my trouble shoot problem

well till then good luck homie.......
Well it turns out that the alarm installer tapped into the Ignition wire on the VATS sysetm is order to give the alarm system power. They should not have done this! They need to get power from another source. The ignition wire needs to have a constant/no break flow/connection. Otherwise, from what I'm told, the computer thinks that the truck is being stolen.
same issue minus the aftermarket system

The passlock on my 06 has been doing this for the past month. The dealer said at first that they couldn't recreate the situation and that all electrical systems passed fine. Its BS to be sitting in the middle of freaking no wheres with your truck not starting. Its currently in for round two at the local chevy dealership and they stated they are fixing it...
Stuck between the alarm shop and the dealer!

I guess the question has to be asked why bother with aftermarket anti theft systems? The factory system is good enough, and you don't have to be stuck between a rock and a hard place when trouble arises. I used to install Clifford, and Hofco high end alarm systems years ago, but that was when factory systems were weak or non-existent. As a repo-man I had to work around alarm systems, and most of them were no trouble. GM's VAT system was a pain in the behind, but if a thief wants your car it will be gone in 60 seconds.

Honking horns and flashing lights are just annoying, they are not a theft deterrent. Auto theft rates in my state have risen. Seven of the nation's Top 10 metropolitan areas with the highest auto theft rates for 2004 are in California. Car alarms have not helped here.
1 - 5 of 5 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.