IBM RT PC Problem Determination Manual page 123

S t e p 161. I B M 5081 G r a p h i c s D i s p l a y
Check that the display is plugged into the wall outlet and that
power is available at the outlet. Use a lamp to check the outlet.
IS THE POWER CABLE SECURELY PLUGGED IN?
YES Go to "Step 169. IB M 5081 Graphics Display" on
page 2-103.
NO STOP. You have found the problem.
Section 2. Hardware Problems 2-95