Display - Motorola GM328 Service Manual

Controlhead GM338 Troubleshooting Flow Chart
2.3

Display

Power Up Alert Tone is OK, volume knob does operate,
indicator/backlight is on but nothing on display
V5 (against 5V)
TP0973 between
-6V and -7V ?
NO
Activity on
Address & Data lines
A0 / D0..D7 / CS1
of U0971?
YES
Check / Replace
C0971 / C0973 / R0972
R0973 / R0974 / U0971
YES
Check LCD Assembly
NO
Check for shortage
U0831 / U0971
3-5