We have 2010 Prius 3 with approx 170,000 miles. We have 3 codes P0031, P0102 and P0403. Took to our local garage and then said that the 3 sensors are on the same fuse. They found the fuse was blown. They replaced the fuse, cleared the codes and took for a test drive. In about 1 mile of driving the codes came back, the fuse was blown again. Did the same thing once more, replacing fuse with the same outcome. Garage said that there appears to be a short somewhere causing this issue and directed us to the dealer for further troubleshooting. I did also try cleaning the MAF Sensor previously. Might the Air Flow Sensor be causing the Short?
Issue found. I took it to my local garage and they found that a Fuse was blown and all 3 sensors are on the same fuse. They felt is was short somewhere and recommended taking it to the dealer. I took it to the Dealer yesterday and they found that one of the Bank 1 Sensor 2 - O2 Sensor wiring was causing the Short, as it was hanging very close or against the Heatshield. They replaced the O2 Sensor and secured the wiring away from the Heatshield and it only cost $500, LOL, but not laughing.
Only three blown fuses for them to recognize what the first one was telling them? I'll never get why people think "replace the fuse that just blew" is a repair technique.
I just had the worst experience ever. Someone replaced the fuse with a larger size one. I thought circuit trace fun was just about to begin and almost over. Blah! Well, EFI No.2 isn't blowing now with the correct 10A installed and all the fuses test just great. I guess so do the relays except the, "what is that long white thing?" There are new codes too, though the P0A2C is still present with the 211 and 530 subcodes. C1259, C1310, U0073, U0293 and U0100 with no US option or VIN present prior to reading the codes. Yeah!!! I want to swear now. I did learn today however, that the ECM is next to the fuse box. Was seriously wondering where the ECU's all are in the gen 3's. I've never had to look; so is new to me with this sabbatical, seems for more than the last month, in the gen 2 world.