Справочник Пользователя для Apple MD094LL/A

iMac (27-inch, Mid 2010) Symptom Charts — Startup and Power 

 2010-09-09

7.  Replace DC power cable, 

which supplies power to 

logic board, hard drive, and 

LED backlight board. Verify if 

system continues to restart or 

shutdown.

Yes

Go to step 8

No

Issue resolved with DC power 

cable replacement.

8.  Hardware-related shutdowns: 

Run latest available Apple 

service diagnostics and verify if 

a sensor failure is reported.

Yes

-If a temperature or a fan 

sensor failure is reported, go 

to step 9  

 

-If a voltage or a current 

sensor failure is reported test 

with known-good power 

supply board. If issue persists, 

replace logic board. 

 

 

 

 

 

 

 

 

No

Setup ASD to loop test suite 

for burn in tests and go to  

step 9. If no failure is found 

after burn in tests, return unit 

to customer for no failure 

found.

9.  Verify if a thermal sensor 

or fan failure is reported by 

diagnostics.

Yes

-If fan not running failure, 

check for fan cable seating 

and retest. If same failure 

after retest replace fan with 

known-good fan and retest. 

If issue does not happen with 

known-good fan, replace 

user’s fan. 

 

-If an over temp failure 

reported, check for cause of 

over temp, like obstructed 

vent, dust in heatsink fin, 

clogged fan and retest. If still 

failing replace part where 

sensor is located (logic board, 

power supply, hard drive or 

sensor cable) according to 

the sensor location table 

in General Troubleshooting 

chapter . Go to step 10

 

 

 

 

 

 

 

 

 

No

Go to step 10

10. Isolate if issue solved 

Verify if shutdown/issue does 

is fixed..

Yes

Issue fixed

No

Replace logic board with 

corresponding symptom: 

-if for thermal error cause 

-if for other cause