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Thread: XBOX360 slim fault

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    Question XBOX360 slim fault

    This is really an electronics related question but specifically I have a slim XBOX360 (250g HDD) that just died suddenly with no error codes, no lights, nothing IE just shut down never to recover. Had to dismantle it to get the DVD out of the drive and there's no obvious sign of any catastrophic failure. The power supply checks out fine and the xbox was tested with another power supply with the same result IE dead as a dodo.

    It would appear that the 5VSB supply is where the fault is with no power getting to the front panel sensors so no startup signal getting back to the power supply. I did trick the power supply into starting up to provide the main 12V output which appears fine but no response from the xbox even with the main supply active so I'm very confident that the fault is on the motherboard. No evidence of a short cct on the standby supply either.

    Any ideas and is this worth pursuing?
    (way out of warranty and the seal was broken in order to retrieve the DVD from the drive btw)



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    A little more info:
    The 3.3V regulated down from the 5V standby supply appears to be the problem and I'm only reading 1.28V on those test points. Having some trouble identifying the actual regulator on this motherboard though.

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    ?
    Last edited by Skepticist; 21-07-14 at 03:17 PM. Reason: double post?

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    If you had another working one to compare that would go a long way to troubleshoot, otherwise your flying blind, as it could really be anything. I have repaired one Slim for being dead, & from memory it was a transistor(FET), but there are many on-board, so even if your measuring a short somewhere, as there are so many components in the cct, its going to be hard to work out....even techs like myself struggle when you dont have cct diagrams or something to compare to...most tests are passive.
    PrecisionMods

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    The story had a happy ending despite the odds against

    Turned out it was a fault on the RF module that overloaded and killed the 3.3V regulator (no idea why they went with a switchmode design for that) - replaced it with a 3.3V low dropout 1A linear regulator (MIC39100), replaced the crook capacitor on the RF module and it's back in service like nothing happened & fully functional

    Got the feeling the MS was trying to hide something by making the box a challenge to get into only to find a lot of components that are hard, if not impossible, to get exact replacements or even datasheets for.
    Last edited by Skepticist; 24-07-14 at 12:28 AM.

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