Keypad Backlight - Motorola GM328 Service Manual

Controlhead GM398 Troubleshooting Flow Chart
3.5

Keypad Backlight

Power Up Alert Tone is audible, volume knob does operate,
display is on but no keypad backlight.
U0871 Pin 25
is toggling ?
YES
Base of Q0943
> 0.7V ?
YES
Collector of
Q0943
>5V & < 11V
?
YES
Check / Replace
Q0941 / R0955 / R0957
Check for shortage
NO
Check / Replace
NO
R0945 / C0943 / R0947
Check / Replace
Q0943 / U0941 / R0941
NO
R0943 / R0949 / R0951
U0871
3-11