Hi - my saga continues - see Replaced 12V battery and still have intermittent Transmission Parking Lock Problem | PriusChat for the backstory. Here's where I am now. Initial problem was "There is a problem with the parking transmission lock. Place the car on a flat surface and fully set the parking brake" So I researched it and replaced the 12V auxiliary battery. Problem went away for one day, then came back. I knuckled under and took the car to the dealer. He said "Master Shift Control Actuator is failing" and wanted $1500 to repair. I declined and picked up the car. (after paying $100 for the pleasure of letting them use their scan tool on the car.) So here are the codes: P0A09 P3102 C2304 C2305 C2306 C2300 Even if we do give the shift actuator a shot I am leaning towards doing it myself. Thoughts?
The shift actuator is a plausible problem based upon the four C230x codes and P3102. If you are lucky, that will be the problem. Other possible problem areas include the transmission control ECU, the transaxle parking lock control relay, the hybrid vehicle ECU, and the power source control ECU. P0A09 is troublesome as that points to a failure of the DC/DC converter within the inverter. If you can make the car READY, measure voltage across the 12V battery. It should be 13.8V or so. If the voltage is substantially lower then the DC/DC converter has failed, hence the inverter will need to be replaced. I suggest you obtain repair manual info at techinfo.toyota.com so that you can research the various DTC yourself.
Thanks Patrick for the info. So I picked up the car Wednesday night at the dealer. The car jockey couldn't get it started, so I walked out to the lot with him expecting to have to disconnect and reconnect the battery. Got in the car, and it started right up albeit with the master warning light lit. Drove it home and parked it. Thursday morning, started fine WITH NO WARNINGS OR ALARMS. Drove to work, perfectly normal. Drove home, normal. Friday (today) drove to work, perfectly normal. Not sure what to think. Obviously, if I never get the warning lights again, I will declare victory. But I know for a long time I will be nervous about recurrence. I am sure it is waiting for my wife to drive the car - next time she does I expect failure and stranding.
