Had problems with mine and cured it with the fix that coolzzy described. Add more solder then wut was on it originally and the foam/rubber piece will keep it from happening again.

 

i work at a chevrolet dealership .. the Fobs SUCK!! and they arent cheap to buy a new one either ..

 

Yesterday I opened both of my fobs to check them out. coolzzy was right about one. The spring to hold the battery in place was cracking off the board. I soldered back together and it works normally every time now. As for the other one, I don't know. The panic and unlock buttons work but the lock button does not.

 

For some reason the lock button on my fobs do not work. Not tried the panic button. It will unlock the car. One is new unused and it does the same thing. I am thinking it is an issue with my car.

 

You might take it with them by your dealer to check it out. Maybe a reprogram will help.

 

I finally got around to fixing mine yesterday. A quick solder job and it works fine again, resoldering the two small connections on the arms of the battery holder, there wasnt much solder on them. Be careful that you dont jump the solder over to the button pad though, its a little close.
I am an electronics/computer engineer and looking at the way these were designed it seems likely that they will fail, I have no idea why GM would have made them this way.
They decided to put weakly soldered electrical connections on the flexible arms of the battery holder, which is something I would never do. It seems they could have just designed the circuit board to use the large solid connection in the middle of the battery holder that does not flex. If another repair is necessary, I may just put jumper wires from the small solder points to the large one, that should last.
And after a quick look, it seems each of the small battery connections power one side of the remote, so if only one breaks it may leave half the remote functional. That is what happened to mine, the unlock button stopped working first.
Heres a couple pics showing the two round holes to solder and the top of the board with the battery holder. I used three small clamps to retain the battery holder and hold the board up.

 

We have an 07 HHR, and both original fobs failed. The problem was the conductive rubber pads that are supposed short across contacts on the printed circuit board. Evidently, the conductive rubber wears off. I have managed to provide at least temporary fixes with adhesive backed aluminum tape. Very temporary fixes with conducting paint. It is possible to make conductive rubber by mixing graphite and rubber cement, which is then applied to the rubber button.

 

The search engine is your friend :) There is lots of information here already on repairing the fobs that have broken solder joints which has been a problem for a few people, and also dirty or worn out contacts (ie: https://www.chevyhhr.net/forums/how-tutorial-library-21/repair-key-fob-remotes-worn-out-contacts-30813/ ).

Great pics btw Prod!

 

After "fixing" the fob numerous times. (Re-solder, aluminum tape, et al) I just wrapped the damn thing in duct tape. It has been working for a week.

 

My HHR fobs are fine, still new. But on my '05 Malibu they are worn out. Been sodered once already, and only one ocasionally works. We really need 2 cause 2 people drive that car.

So I decided to try an aftermarket keyless system. Installed with 2 fobs will be cheaper than replacing just one GM fob. Hopefully this works