Epson 386SX - Manual (Page 204)

Monochrome Display Adapter and CRT Check
Use this option to verify the operation of a monochrome display
adapter, VGA, or EGA card attached to a monochrome
monitor. This test includes several checks that allow you to
identify particular problems related to the monochrome display.
You can select the individual checks from this menu:
MONOCHROME DISPLAY ADAPTER AND CRT CHECK MENU
0 - Exit
If an error occurs during any of these tests, record the error code
and message, or print them out. Then contact your Epson dealer
or service center.
When you finish testing the device, select 0 to exit.
Monochrome Adapter Check
To check the monochrome adapter, select 1. The program
checks the video RAM (display memory) on the display adapter
by writing certain data to memory, then reading it back and
comparing it to the written data. The program also tests the
video enable signal of the display controller chip.
C-12 Performing System Diagnostics