Motorola CM Series Service Information page 15

Controlhead CM140/CM340 Troubleshooting Chart
1.3 Button/Tones Select Error (Page 2 of 2)
on DTMF keys
Button/Tones Keys
Key_Col
Voltage
(TP401)
0.008 V
0.675 V
1.346 V
1.997 V
2.650 V
3.300 V
A
Right
No
Voltage
?
YES
Okay
0.008 V 0.675 V
4
8
#
Left Key
Down
P1
Does Q812
No
on Control Head
operates well
?
YES
Replace U803
on Control Head
Key_Column Voltage TP401
1.346 V 1.997 V
1 2
5 6
9 0
C B
Right Key
P2
Replace
Q812
2.650 V 3.300 V
Up
3
7
*
A
Idle
3-3