Testing the AC Adapter (8543)

1.  If a noise can be heard from the AC adapter when it is  plugged into line voltage, replace  the AC adapter.

   If a noise still comes from the AC adapter, suspect  the computer.
    If not, the AC adapter has a problem. Replace the AC adapter with  the original one, then go to the next step.

2.  Measure the output voltage at the plug of the AC adapter cable.

Pin	Voltage (Vdc)
1	+14.3 to +15.8
2	Ground

If the voltage is not correct, replace the AC adapter.