Apple imac 17in 1ghz Servicehandbuch

iMac (17-inch Flat Panel, 1GHz) Troubleshooting -

No Power Symptom Charts

11. Remove the bottom housing.   Check that all the cables on the logic board are securely connected. Pay 

special attention to the video connector. Power on the unit again. If you still have no power, go on to the 

next step.

Warning:  Whenever the bottom housing is opened for service, you must do two things:

• You must clean the original thermal film from the surfaces joining the thermal interface layer and 

reapply thermal paste to the thermal pipe.

• The bottom housing has four torx screws that must be tightened to at least 17 in.-lbs. If you do not 

have a torque driver, you will have to make sure these screws are tightened by hand FIRMLY, BUT 

NOT FORCIBLY. Or, purchase the service tool (076-0899) in order to ensure the thermal pipe is 

firmly mated with the top base. If the bottom housing is not securely attached to the base in this 

fashion, the CPU may overheat and become damaged.

12. Check power supply output. Disconnect the power supply cable from the logic board. Measure power at 

the power supply connector by touching the black probe to the ground pin, and using the red probe to 

measure power at the pins indicated in the graphic below. Did you measure +12v at each point? If yes, 

replace the logic board. If no, replace the power supply.   

13. Replace the inverter board.

14. Replace the neck assembly.