Motorola MOTOTRBO XPR 7550e - Page 57

Troubleshooting Charts 5-27
Figure 5-27.Troubleshooting Flow Chart for Keypad
Front Housing Functional Test
Display
OK
Keypad
Button
OK
Backlight
OK
High
Current
@ Main
board
Keypad and Side
Buttons contact
to ground ?
MDSINK1,
MDSINK2 and
KPSINK OK
Keypad Flex
Assembly OK
Display
controller lines,
1.8V and 3.3V OK
No
Yes
Yes
No
Yes
Check U3000 & U1000
Inspect display and flex
assembly
No
Check U1000
Yes
Yes
Replace flex
Yes
Yes
No
Check U3000
No
Inspect LEDs
Yes
No
Inspect Main board
No
Reattach the flex
End Test
No