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iMac 21.5 "& 27" - error 4SNS / 1/40000000: TH00-9.000 after replacing HDD

Discussion in 'Casie Studies' started by Administrator, Mar 12, 2018.

  1. Administrator

    Administrator Administrator Staff Member

    Apr 6, 2017
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    iMac 21.5 "& 27" error 4SNS / 1/40000000: TH00-9.000 after replacing HDD

    4SNS / 1/40000000: TH00-9.000 error after replacing the hard disk in the following Apple models that do not have an external disk temperature sensor :
    - iMac 21.5 "A1311 (model 2011)
    - iMac 27 "A1312 (model 2011)
    - iMac 21.5" Retina A1418 (models: 2012, 2013, 2014, 2015)
    - iMac 27 "Retina A1419 (models: 2012, 2013, 2014, 2015)

    My method does not require any financial outlays in the form of adapters, additional cables or modules, is non-invasive for computer cabling, fast and 100% effective. It eliminates all of the symptoms described below, including displaying an error in AHT.


    - very slow operation of the operating system,
    - task kernel 100% and more in the Activity Monitor (constant, full CPU load),
    - high fan speed (on the A1311 / A1312 models of the HDD fan, on the A1418 / A1419 models of the main fan),
    - error 4SNS / 1/40000000: TH00- 9,000 in AHT tests (Apple Hardware Test - triggered by holding Alt + D keys while the computer is starting up).


    New hard drives that are not branded with the Apple logo are inconsistent with the Apple SATA standard that provides for a temperature sensor located on the disk electronics board. Apple discs use pin 11 SATA power connector (15-pin) to output voltage from the temperature sensor. Below is the difference between a standard SATA connector and an Apple SATA connector:
    Fig. 1 and 2 - pinout of the SATA power connector (on the left a standard pinout, on the right Apple pinout)


    Just before mounting the drive, connect pin 11 to pin 12 of the SATA power connector with a tin drop, as on the pictures below: Fig. 3 and 4 - SATA connector pins 11 and 12 (2.5 "on the left, in which the soldering points of the connector are available without disassembling the electronics, on the right a 3.5" disk, in which the soldering points are not available from the outside and it is required to disassemble the electronics board) ==========

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