IBM Aptiva 2142 - Manual (Page 126)

Display Self Test
Be sure the monitor has been turned on for approximately 5 minutes before
you start the Display Self Test.
Run the test as follows:
1. Power-off the system unit and monitor.
2. Disconnect the monitor signal cable from the system unit.
3. Power-on the monitor.
4. If the monitor power-on LED is not lit or flashing, or you do not see one
of the indications below, replace the monitor.
For MM55, Type 2116 monitors:
The Red/Green/Blue raster will display.
The Green LED will be on solid.
For MM75, Type 2128 monitors:
The screen will be full white.
The orange LED will be on solid.
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