Volume/Channel Error - Motorola APX 1000 Detailed Service Manual

Troubleshooting Charts: Volume/Channel Error
5.6

Volume/Channel Error

Verify if VCC_1.85 present
on keypad at TP2005
Is V_Ext_1.85
present at C2116?
Replace Keypad flex
Verify all connectors from
J2302 to frontkit flex are good.
No
Yes
Is 1.85V
present?
No
No
Refer troubleshooting
Yes
Volume / Channel Error
Remove SH13
Probe TP2111 and
TP2110 with scope
Is voltage level
Yes
1.85V when
rotating switch?
Yes
Replace frontkit flex
guide 5.4.4
Observe if any noise
on waveform
Is noise
present?
No
Check U21000,
U21001, U21002 and
U21003 circuitry.
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