This Game Boy Test Cartridge was given to technicians in order for them to test Game Boy systems for defects.  It runs some very simple programs and has the following tests on it's main menu:

•   Auto Test
•   Screen Test
•   Controller Test
•   Scroll Test
•   Sound Test

This test cartridge will work on all Game Boy consoles, most notably the function that detects button-presses to ensure they’re working; note, though, that this particular cartridge cannot test the shoulder buttons on Game Boy Advance consoles, but can still evaluate the other buttons.

Menu

The main menu says:

GAME BOY TEST MENU

1 AUTO TEST
2 SCREEN TEST
3 CONTROLLER TEST
4 SCROLL TEST
5 SOUND TEST
PRESS SELECT
PRESS A TO START
c 1990 NINTENDO

AUTO TEST

RAM TEST PASS
PRESS A TO STEP
TO NEXT TEST

SCREEN TEST

SCREEN TEST
PRESS A BUTTON
TO BEGIN TEST
THREE PATTERNS
WILL APPEAR
EVERY 3 SECONDS
TEST FAILS IF ANY
LINES ARE BLANK

CONTROLLER TEST

PRESS
EACH
BUTTON

This shows a picture of the game boy with the controller buttons on it. When you press a button it lights up the button in the picture and makes a different tone beep for each button pressed. After you press all the buttons it says:

TEST
PASS
 
PRESS
A AND B
FOR
NEXT
TEST

SCROLL TEST

PRESS B TO SCROLL
CHECK FOR A SMOOTH
SCROLL

When you press B the screen with the text scrolls down and to the right. This reveals the following text:

PRESS A TO STEP
TO THE NEXT TEST