donbrew

I don't know what you mean by "they used their fancy tool exactly like in the manual" . The 2008 manual does not mention using any tool.

The EL-50448 tool is used to excite the sensors AFTER the fob is used to put the RCDLR into learn mode. It serves the same function as changing the pressure.

I don't know why the tires store was able to get the horn to honk on all 4 wheels. The usual bad behaviour is to honk twice (time out) on the first.

Once the the new firmware/calibration is installed it doesn't need it again. Here is a link to the TSB TSB 08-03-16-001B the heading says Cobalt, but scroll down to vehicles affected.

Eddy Strait

Hi Guys, finally got around to taking this into the dealer this morning. They said $140 to walk in the door basically. I gave them the TSB that you guys provided and they were intrigued that I had it. I then explained to them everything we talked about and said this was only happening on some 2008 models, etc... Gave them a big sob story how I should not have to pay them a single penny because all I did was change my battery (w/o plugging a backup power into the cigarette lighter) and get 4 new tires and that is when this started happening. After waiting almost 2 hours, they brought it back to me and said they fixed it and said "no charge". Can you believe that? I said, did they have to reprogram the firmware (as noted in the TSB), and the service advisor just nodded (but I'm not sure she really knew what the tech did to fix it, but presumably just that. Phew! What a crazy runaround and huge headache!! Thanks guys for all of your help, you're awesome! :)

RJ_RS_SS_350

That's great!

Oldblue

All fixed, now keep it clean and drive it often!!