2005 Prius Error Codes

sounds like a scam. he should have told you beforehand. try disconnecting the 12v neg for a few minutes and see if they come back

 

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How much did you pay for the used HV Battery replacement, part price wise? I hope only a few hundred (<$800) MAX. Some people have been able to find a new OEM HV Battery for $1600; not all dealers will sell to the public and price match other Toyota dealer online part prices. 2k1Toaster sells a NEW cylindrical module replacement for $1600.

Learn to perform an Internet Search: "Toyota DTC C1241". This will give you a fast result, that will point you in the right direction. It can be cumbersome to find the codes in the factory service manual.

C1241- low 12V battery
C1256- low accumulator pressure
U0123- lost communication w/ Yaw rate sensor
U0124- lost communication w/ lateral acceleration sensor module

There are subcodes for U0124. Immediately to the left of "U0124," there appears a "snowflake (what everyone seems to call it here)" Click the "snowflake"​

U0126- lost communication w/ steering angle sensor
B1421- solar sensor (IGNORE, no harm will come. This sensor wasn't receiving enough bright sunlight for its liking. The auto AC setting uses this sensor.)

IMO, everything seems to be related to a low 12V battery.

1) The mechanics drained the 12V battery down low.
2) And/Or the current 12V battery was low/weak/old when they started working on the car.

Do:
Clear all codes.
Then recharge/replace the 12V battery.
Recharge the battery with a 12V smart AGM compatible charger.
READ: Is my inverter coolant pump slowly failing? | PriusChat

Post #5) How to apply a load to get a more accurate State of Charge (SOC) reading.
Post #8) SOC chart, AGM compatible battery chargers (which you already have).​

If it were me, I would avoid that shop. All those codes have no immediate bearing on the HV battery!