I had the lock out today, took the cover off and spayed some LPS Red Sticky grease on everything. The motor doesn't seem to have enough power to lift the locking mechanism. I sat here and debated what to do for awhile and ended up ordering new " " through Amazon. $145.37 after taxes delivered in a couple of days. I didn't try to remove the motor and give it a good cussing figuring I'd never get it all back together correctly. I might try that after get the new one and prove it will work. I didn't see any sign of moisture or corrosion anywhere. All you get from the lock/unlock signal is short pulse. If the motor doesn't have the power to move the linkage, it's done till the power is reversed. This motor is better at pulling the lock knob down than it is at pushing it up. Moving it by hand doesn't seem much different in either direction. I went with the Standard Motor Products lock figuring it couldn't be any worse than the OEM lock that failed and might work even better. I looked at "fc-280sc-18180" motors on Ebay and while they're between $4 and $15 depending on if they have a gear on them shaft or not, they all look like they'd have to come from China and with shipping the way it is, I decided to place the order with Amazon and be done with it.
Thanks for all the comments with leads to previous fixes and I'll copy and paste the fix linked to in another topic into a document for later reference. These forums are great for exchanging information. I haven't run into many problems that someone hasn't already posted a fix for. My daily driver is a '97 Aerostar and that forum has been a lifesaver many times. Thankfully, I haven't had to do many repairs on the HHR so far - less that 60k miles on it right now.
I'll be back with the rest of the story after I get the new lock next week.

 

It broke my heart to pay the $145 for a new door lock but it fixed the problem so I guess I can't complain. At least I didn't have to pay a dealer's prices for parts and labor.