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  1. #1
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    820-3462 no battery detected

    smbus_smc_5_g3_sda keeps cycling from 0v to 3v
    smbus_smc_5_g3_scl is 0v
    i've replaced D6950 and the ISL and reflowed the smc and still no joy

  2. #2
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    Re: 820-3462 no battery detected

    Are there any shorts on these lines?
    Do they still show 0v all the way back to U4900?
    Are the pull-ups OK?

  3. #3
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    Re: 820-3462 no battery detected

    the pull-ups were checked for 2k resistance and the ISL and d6950 were removed. they were are the only things in the path. the SDA line goes from 0v the 3v every other second and the SCL is 0v all the time

  4. #4
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    Re: 820-3462 no battery detected

    What is diode mode reading on those two lines (SCL and SDA)?
    Do you get voltage on the pullup resistor (at least on the one side)?

    Something is pulling the SCL line down, or it isn't being supplied with voltage at the first place.
    Remove the SMC and check if the voltage goes up.

    And of course, is the battery known good? I hope you are measuring with the battery disconnected.

  5. #5
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    Re: 820-3462 no battery detected

    bad smc

  6. The Following User Says Thank You to kjchatman For This Useful Post:

    mitchW (09-19-2019)

 

 

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