TPMS Fault Troubleshooting

I had four new tires put on my fiances 07 Prius about 4 weeks ago. Got the car back and drove over 2,000 miles to Florida and back and had no issues. Last week she tells me her TPMS light came on. I had her visually inspect the tires and she said they didn't look flat. I checked them when I got home and they were all between 33 and 35 psi. I would imagine if the shop had messed up a sensor I would have had a TPMS light immediately, not 3 weeks later. It's a blinking light when the vehicle is first turned on, then it goes solid. The manual indicates this means there is a fault in the system.

Is there any way a competent DIY'er can troubleshoot this at home without taking it to the dealer? I have an INNOVA 3130 OBD-II Scan tool, but I'm guessing there are no generic OBD II codes for TPMS sensors. The scanner has a menu option for enhanced DTC's for specific vehicle manufacturers, Toyota included, but again I'm not sure if anything will show up from the TPMS. When she gets back I will try, and probably disconnect the 12V to reset it, but beyond that, is there anything else I can do short of taking it to the dealer?