IBM 6151 Maintenance And Service Manual page 348

Step 2
Try to set the Brightness and Raster Test control to the desired
level.
IBM
*
0
t-------'---'-------,
AJZB204
WERE YOU ABLE TO SET THE BRIGHTNESS CONTROL TO
THE DESIRED LEVEL?
NO Record SRN 26-600-430; then go to "Step 6" on
page 3-6000-6.
YES Go to "Step 4" on page 3-6000-4.
3-6000-2 Service Manual