2007 Prius C2318 and C1241 and some more.....

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by Classic Car Guy, Jan 8, 2026 at 3:09 PM.

  1. Classic Car Guy

    Classic Car Guy Active Member

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    Everything was running fine, dashboard is clear then all of a sudden all these lights came out of the dash. Besides all the lights came out while its still driving fine heading towards home. After 7 minutes I heard the traction battery cooling fan turned on which I hardly hear and started driving a limp mode. As soon as I got home, I just parked it then the next day I took it to O'Reillys to get a scan check and this is what I got from them. This morning I went to check and it still starts. The traction battery cooling fan is not running anymore like when I parked it. I drove it around again and I looked at the dash while all those problem lights are still on. I looked at the generator screen and seems like still running but its not like the regular indication I get. Sometimes the traction battery indicator bar goes all the way to Green Full Far. Then sometimes it changes to Blue Mid Bar then Low. Then its slowly goes up again. As soon as I was going home after 10 minutes, I heard the traction battery turned on again while I was pulling in the drive way. I work on my car is a scheduled / mileage manner. As far as I know, none of those light nor trouble codes were there before.
    What could it be?
    My car is a 2007 Prius Pacific Northwest Package 6 (Not Touring) with 174,186 miles.
    Here are the codes written in the diagnosis:
    C2318
    C1241
    U0073
    U0123
    U0124
    U0126
    U0293

    Diagnosis 1.jpg

    Diagnosis 2.jpg
     
  2. Tombukt2

    Tombukt2 Senior Member

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    Have your 12 volt battery low tested and be assured that it is good usually all these communication issues is over Power 12V power.
     
    xw20_driver likes this.
  3. Classic Car Guy

    Classic Car Guy Active Member

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    If I need to replace the battery. Is AGM better than True Start?
     
  4. Tombukt2

    Tombukt2 Senior Member

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    Eryone should have an AGM .true start is a brand name AGM is chemistry make up like sodium
     
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  5. Classic Car Guy

    Classic Car Guy Active Member

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    you mean to say true start is agm battery? the local store tested the battery last night and it failed. Along the way they asked me if the battery is AGM. I said no. They said if its AGM, they need to restart the test procedure in a different way.
     
  6. xw20_driver

    xw20_driver Junior Member

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    Toyota TrueStart 12V batteries can be either flooded lead acid or AGM. The difference is the battery type and the shop test equipment indeed could have different test protocols if the battery is AGM or flooded. You should investigate exactly what battery is in your car or post a picture here to confirm. The original spec 12V battery part numbers S46B24R (for smart key) or S34B20R (non smart key) should both be AGM type batteries.

    EDIT: Typo corrected S46B34R to S46B24R
     
    #6 xw20_driver, Jan 9, 2026 at 1:06 PM
    Last edited: Jan 9, 2026 at 1:26 PM
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  7. Classic Car Guy

    Classic Car Guy Active Member

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    This is the one they gave me True Start Part #: 00544-21171-325
    seems like S46B24R
     
  8. Tombukt2

    Tombukt2 Senior Member

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    Usually they proud of it . It's all over battery in text .
     
  9. Classic Car Guy

    Classic Car Guy Active Member

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    Toyota gave me the same one which is the original on True Start S46B24R. I installed and ran it. after 12 minutes all the light went back on.
    What does this symbol means?

    Diagnose symbol.jpg
     
  10. Brian1954

    Brian1954 Senior Member

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    Look in the Toyota owners manual, and you will find the answer to your question.
     
    #10 Brian1954, Jan 9, 2026 at 9:13 PM
    Last edited: Jan 9, 2026 at 9:30 PM