This has a timing chain, so no timing belt. It has electric power steering, so no belt for that, either. So, how many belts are left and what do they turn? Is there just one serpentine belt, and that failed here?

 

Alternator.

 

Most new cars only have one belt. On the HHR it runs the alternator and the air conditioning compressor.

When you change the belt, you might want to change the tensioner and and idler pulleys.