IBM PS/2 CL57 SX Hardware Maintenance Reference page 20

5.1 Checking the AC Adapter
If the Power-On indicator is not on, check the power cord of the AC
adapter for proper installation and continuity.
1. If any noise can be heard from the AC adapter when it is plugged into
line voltage, replace the AC adapter with a new one.
If no noise can be heard from the adapter, go to Step 3.
2. If the noise still comes from the new AC adapter, suspect the system
unit. Replace the AC adapter with the original one, then go to the
next step. If no noise comes from the new adapter, the original
adapter has the problem.
3. Unplug the AC adapter cable from the system and measure the output
voltages at the plug of the AC adapter cable.
of the volt-ohm meter to pin 3 during the measurement.
+------------------------------------------------------------------------+
¦ Pin
+------------------------------------+-----------------------------------¦
¦ 1
+------------------------------------+-----------------------------------¦
¦ 2
+------------------------------------+-----------------------------------¦
¦ 3
+------------------------------------+-----------------------------------¦
¦ 4
+------------------------------------------------------------------------+
If the voltages are not correct:
1. Unplug the AC adapter from the ac power outlet and leave it for a
few minutes.
2. Plug the AC adapter into the ac outlet.
3. Measure the output voltages of the AC adapter.
4. If the voltages are still not correct, replace the AC adapter.
If the voltages are OK, plug the cable into the system and try the
failing operation again.
If the problem still remains, replace the voltage converter.
problem disappeared, suspect the installation and continuity of the AC
adapter cable.
IBM PS/2 Model CL57 SX HMS
Checking the AC Adapter
Connect the minus lead
PICTURE 3
¦ Voltage (V dc)
¦ +18 to +22
¦ +17 to +21
¦ GND
¦ Communication GND
¦ Copyright IBM Corp. 1992
5.1 - 1
¦
¦
¦
¦
¦
If the