Motorola APX 7500 Detailed Service Manual page 131

Troubleshooting Charts and Error Codes Troubleshooting Charts
Apply an on-channel signal at -47dBm,
modulated by a 1kHz tone at 60% rated
system deviation, to the Consolette receiver.
Is there a 1kHz, ~300
mVrms tone at the 3.5mm
audio jack?
Yes
STOP
Figure 7-13. Audio Jack RX - A
68009482001
No
Is the APX7500 mobile
operating properly?
Yes
Is the RX Codec Adjustment
in the Consolette Configuration
properly tuned?
Yes
Is there a 1kHz,
~300mVrms tone at U1810-
6 on the Consolette
Mainboard?
Yes
Is there a 1kHz,
~300mVrms tone at
R1883?
Yes
~300mVrms tone present
Refer to the APX7500
Detailed Service
No
Manual for correct
operation and
troubleshooting.
Refer to the "Receive
No
Audio Tuning –
RX_AUDIO" section of
the manual
No
Reprogram/Replace Consolette
Mainboard.
Verify R1878, U1810,
No
C1820, R1877, R1876 &
C1821 are placed properly.
Is ~3.3Vdc
present at
U1810-2?
Yes
Does U1810-1
measure ~2.8Vdc?
Yes
Replace U1810.
There may be an issue with the
No
internal board routing of
VCC_3.3V.
Reprogram/Replace Consolette
No
Mainboard.
September 9, 2011
7-15