Acer B1-720 Service Manual page 31

4. Hardware Keys Test
Press the volume up and volume down keys. The Vol - and Vol + text on the screen will
change if the HW keys work and auto pass the test.
Or, judge the test by tapping the "Failure" button or touch "Retest" to retest.
5. Front Camera Test
Aim the front side of the device at an object. Tap "capture" to test the picture taking functionality
and the quality of the picture.
Tap "Pass" if the test passes, "Failure" if the test fails, or "Retest" to redo the test.
Diagnostic Utilities
Figure 2-7. Hardware Keys Test
Figure 2-8. Front Camera Test
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