Main Display Failure - Motorola APX 5000 Service Manual

Troubleshooting Charts: Main Display Failure
5.6

Main Display Failure

No Main Display
Replace LCD
Problem
Solved?
Check DC on the following:
Signal
V_EXT_1.85
V_2.775D
Are Voltages
correct?
Proceed to DC
Flowchart
Yes
No
Probe Point
Pin 12 of J2304
Pin 2 of J2304
Signal
Yes F_DISP_RW
F_DISP_DATA_CMD
F_DISP_RW_EN
OMAP_RESET
No
End
Check the following signals:
Probe Point
R2335
R2347
R2342
R2343
Signals Correct?
Check Vocon to front
display connector J2304
Connectors
Good?
Replace Back Chassis
Subassembly
Level
0V
1.85V. Hi = Data. Low = Command
1.85V. 4 MHz Square
1.85V
No
Replace Vocon
Yes
Replace Board/
No
FPC Containing
Connectors
Board
Yes
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