5-30
Troubleshooting Charts:
TX Audio Error
5.12 TX Audio Error
Internal Microphone
Rear MIC is
inoperative
Replace Rear
Mic
Measure Mic Bias at R6403
Isolate problem, replace rear mic
4.5 < V < 4.9
Inspect SSI_Red_Tx_Codec
audio data to OMAP by using
Oscilloscope at R6118.
Are Parts Solder
Connectons and
Placement Correct
Replace or Repair
Parts.
Replace Main Board
Is rear mic functional
Is SSI Audio
Data Present
Replace Main Board
View SSI Signals
at R2819, R2807, and
R2808 using an Oscilloscope
Inspect MIC Bias Circuit
U6402 and Supporting
Circuitry
Replace Main Board
Yes
No
Yes
No
Yes
Yes
No
No
Synopsis
This failure specifically refers to the rear microphone
but this flowchart can be used to diagnose front side
microphone also. All mics mentioned above have
similar paths and have very limited differences.
Please refer to schematic and theory of operation
section for differences
Summary of Contents for APX 2000
Page 1: ...APXTM TWO WAY RADIOS APX 1000 APX 2000 APX 4000 APX 4000Li DETAILED SERVICE MANUAL ...
Page 4: ......
Page 6: ...iv Document History Notes ...
Page 8: ...Notes vi Commercial Warranty ...
Page 10: ...Notes ...
Page 22: ...xiv List of Figures Notes ...
Page 226: ...6 64 Troubleshooting Waveforms LF CW on Spectrum Analyzer Notes ...
Page 688: ...Index 4 Index Notes ...
Page 690: ...ii Notes ...
Page 700: ...xvi List of Figures Notes ...
Page 806: ...5 50 Troubleshooting Charts PA Failure Notes ...
Page 1008: ...8 178 Schematics Boards Overlays and Parts Lists Transceiver RF Boards UHF2 84012621001 Notes ...
Page 1062: ...8 234 Schematics Boards Overlays and Parts Lists Keypad Board M2 and M3 PC000261A01 Notes ...
Page 1064: ...ii Notes ...
Page 1068: ...Notes A 4 EMEA Warranty Service and Technical Support Further Assistance From Motorola ...
Page 1090: ...Glossary 10 Glossary Notes ...
Page 1094: ...Index 4 Index Notes ...
Page 1095: ......