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Meaning of A/C ECU diagnostic code

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by drive2much, Jul 10, 2010.

  1. drive2much

    drive2much Junior Member

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    Having A/C problems. Ran the self-diagnosis function on the air conditioning ECU. Got a flashing 21 for the sensor check. Anybody know what that means? Thanks!
     
    #1 drive2much, Jul 10, 2010
  2. Patrick Wong

    Patrick Wong DIY Enthusiast

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    B1421/21 means that there is an open or short in the solar sensor circuit. The problem areas include the solar sensor, the wiring harness, and the AC amplifier.

    The repair manual notes that if you are doing the check in a dark area, that DTC might come up without an actual failure. In that case the DTC should go away after ~8.5 minutes.
     
    #2 Patrick Wong, Jul 10, 2010
  3. 3prongpaul

    3prongpaul Hybrid Shop Owner, worked on 100's of Prius's

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    I would say 60-70% of Gen2's that I scan with Techstream have a B1421 "solar sensor" error.

    Ignore it, unless you specifically have an AC problem.
     
    #3 3prongpaul, May 30, 2011
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