IBM RT PC Problem Determination Manual page 41

Step 4. Operating Instructions
Once the diagnostics are loaded, the DIAGNOSTIC OPERATING
INSTRUCTIONS screen is displayed. "Diagnostic Function Keys"
on page A-2 provides a description of the diagnostic function keys.
Notes:
1. If the display is blank, check the display's Brightness and
Contrast controls and, if present, the power switch.
2. If your system is connected to a 5085, the keyboard belongs to
the 5081 Display at power on. If you have not switched the
keyboard to your display, press and hold the Alt key, then press
the Sw Keybd key.
The Sw Keybd status light on the keyboard should now indicate
PC mode. For more information on the 5085 see
PC Graphics System Operation
IS THE "DIAGNOSTIC OPERATING INSTRUCTIONS"
SCREEN DISPLAYED WITHOUT ANY OBVIOUS DISPLAY
PROBLEMS?
YES Read the screen and press Enter. CONTINUE to the
next page.
NO Go to "Step 50. Power" on page 2-40.
.
Section 2. Hardware Problems 2-13
IBM 5080/R T