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Prius troubleshooting help P0606

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by RMB0001, Jun 16, 2023.

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  1. RMB0001

    RMB0001 New Member

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    Hello I know the code is saying that the ECU lost connect and I have been checking wires but can't get anything from it. This code came up a month ago and drove it around for about 1k miles and the code came up and erased it again. And now it's been about 450 miles and came up again any suggestions.
    If it's wires then let me know which wires to check. And if ECU then I'm a bit scared of it.
     
    #1 RMB0001, Jun 16, 2023
  2. ChapmanF

    ChapmanF Senior Member

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    I don't think there are many wires to check. According to the repair manual, P0606 comes from an ECM internal self test, and pretty much means the ECM is broken.

    Toyota Service Information and Where To Find It | PriusChat

    It does have you check for other trouble codes first. That is, if you have any other codes besides P0604, P0606, P0607, or P0657 (the ECM internal fault codes), they would have you go resolve whatever other codes you have, first, and then see what happens.

    But if you only have code(s) from among those four internal ECM ones, they say replace the ECM. That doesn't have to be scary, you just get one that isn't broken, and unplug the broken one, and plug in the non-broken one.
     
    #2 ChapmanF, Jun 17, 2023
  3. RMB0001

    RMB0001 New Member

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    I do not have any other codes, P0606 is the only code and gives me a check engine light. If I did just get an ECU from the junk yard and replaced it, I would have to reprogram the new ECU, right?
     
    #3 RMB0001, Jun 17, 2023
  4. dolj

    dolj Senior Member

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    For the engine control module (ECM), I believe there is no programming required. The repair manual indicates you simply remove the old one and install the replacement.
     
    #4 dolj, Jun 17, 2023
  5. mr_guy_mann

    mr_guy_mann Senior Member

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    A Gen2 ECM is plug & play- no programming or relearning. You can carefully flip the ECM connectors around to test the "new" ECM before removing the old one.

    Might want to clean the throttle body bore as well. You'll erase the throttle "learned adaptation" which can cause a problem when starting the ICE.

    Posted via the PriusChat mobile app.
     
    #5 mr_guy_mann, Jun 17, 2023
  6. RMB0001

    RMB0001 New Member

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    Sweet thank you guys I'll keep you all updated and thanks again for the info
     
    #6 RMB0001, Jun 17, 2023
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