Fluke 43B - Display and Backlight Test

43B
Service Manual
4-4
4.4 Display and Backlight Test
Before doing the tests, you must reset the test tool to put it in a defined state.
Proceed as follows to reset the test tool:
• Press
to turn the test tool off.
• Press and hold
.
• Press and release
to turn the test tool on.
Wait until the test tool has beeped twice, and then release
When the test tool has
beeped twice, the RESET was successful.
Proceed as follows to test the display and the backlight:
1. Press
to turn the test tool on.
2. Remove the adapter power, and verify that the backlight is dimmed.
3. Apply the adapter power and verify that the backlight brightness is set to maximum.
4. Press
to leave the STARTUP screen.
5. Press and hold
.
6. Press and release
.
7. Release
The test tool shows the calibration menu in the bottom of the display.
Do not press now! If you did, press twice to turn the test tool off and on,
and start at 4.
8. Press (PREV) three times.
The test tool shows
Contrast (CL 0100):MANUAL
9. Press (CAL) .
The test tool shows a dark display; the test pattern as shown in Figure 4-1 may not be
visible or hardly visible.
Observe the display closely, and verify that no light pixels are shown.
Figure 4-1. Display Pixel Test Pattern