I suppose during the day, you could just tow to the dealer and let them deal with it. The last 2 of these calls we had were at night, so that changes things. Obviously, you cannot just leave someone's car running with the keys in it in the parking lot at a dealership when they are closed. That is a car theft waiting to happen, and certainly a liability to the towing company that just leaves it there. With that said, these get brought to OUR FACILITY overnight (or over weekend) and delivered to the dealer on the next business day. These will most likely be Cross Country calls (GM Roadside) so this is actually a great way to not only protect their car and your liability, but to increase your revenue for the call as well.
Make sure you call them (Cross Country) for additional charges! You will end up with the original PO which will cover the tow to your storage location, and whatever number of days storage is necessary until the dealer reopens. You will need to request a second PO for the labor of disabling the car and making it shut off, which generally will just get classified as a jump start PO. Fine by me, its easy money. You also will need a PO for the second tow, to cover taking it to the dealer from your shop. If the dispatcher you talk to seems clueless, ask to speak to their supervisor. I hear they have a lot of new people and they don't understand the whole concept of tow and store, and retow, etc. I ran into that the other day with this one, and his supervisor took over the call and he knew exactly what we were trying to do.
Keys are stuck in ignition, will not turn off from the "run" position
Open the hood of the vehicle and locate the fuse/relay box on the driver's side
Remove the fuse/relay box cover, and locate the RUN/CRANK relay
(Pulling the fuel pump relay would eventually starve the engine and make it stall, but I would rather kill it instantly by pulling the ignition relay)
If you are standing in front of the car, this will be the gray colored relay located in the lower left corner
The underside of the fuse box cover has a diagram to show you what each fuse and relay is for.
Close up view
I like to lay the pulled relay in the cover, and leave it on the floorboard of the car. This way the mechanic can't miss it.
Open the trunk, and disconnect one or both of the battery terminals. The battery is under the trunk carpet. I believe it was a 10mm nut on the terminal.
Just because I don't believe in assuming that others will know whats going on, I will leave a detailed note explaining what I removed/disconnected.
I hope this helps someone! Thanks for looking.