User Guide

Troubleshooting General/ Testing for Power - 9
At the Power Supply Board Fuse
First remove the top access cover and then remove the CRT EMI
shield to access the power supply board.
±
Warning:
You must unplug the iMac to test do a continuity test
at the power supply board fuse.
Note:
You will need an ohm meter do a continuity test on the power
supply board fuse. Refer to the picture on the next page to locate
the necessary test point referenced in the following procedure.
Unplug the computer to take this reading. Using an ohm meter,
touch the red and black probes to the two metal points at location
F901 and check for continuity (reading of “0”). Any other
reading than “0” indicates a bad fuse, which should be replaced.
The figure on the following page shows how to take the reading.
Testing the Power Supply Board Fuse