Chapter 5 Troubleshooting Charts; List Of Troubleshooting Charts; Table 5-1. Troubleshooting Charts - Motorola APX 3000 Detailed Service Manual

Chapter 5 Troubleshooting Charts

This section contains detailed troubleshooting flowcharts. These charts should be used as a guide in
determining the problem areas. They are not a substitute for knowledge of circuit operation and
astute troubleshooting techniques. It is advisable to refer to the related detailed circuit descriptions in
the theory of operation sections prior to troubleshooting a radio.
5.1

List of Troubleshooting Charts

Most troubleshooting charts (see
noted, but it is good practice to verify supplies and grounds to the affected IC and to trace continuity
to the malfunctioning signal and related circuitry before replacing any IC. For instance, if a clock
signal is not available at a destination, continuity from the source IC should be checked before
replacing the source IC.

Table 5-1. Troubleshooting Charts

Troubleshooting
Main Troubleshooting
Main Troubleshooting Flowchart
Power-Up Failure
Main Board
B+ Incorrect Voltage
Low LDO10 V_3.3 Voltage
Low LDO3 V_1.55 Voltage
Low LDO8 V_5.0A Voltage
Low VBUS2 Voltage
Low V_SW_1.4 Voltage
Low V_2.23 Voltage
Low V_SW_3.6 Voltage
Low V_SW_5 Voltage
Low V_EXT_1.85 Voltage
DC Supply
DC Supply 5 Volt Failure
DC Supply 3.6 Volt Failure
DC Supply 3 Volt Failure
DC Supply 1.85 Volt Failure
Table 5-1) end up by pointing to an IC to replace. It is not always
Table 5-1. Troubleshooting Charts (Continued)
Page
No.
DC Supply 1.8 Volt Failure
DC Supply 1.5 Volt Failure
5-3
DC Supply 1.4 Volt Failure
Button
5-4
Side Button Error
5-5
Audio
5-6
External Audio
5-7
External Mic Failure
5-8
Keyload/ Secure Hardware/ Memory
5-9
Keyload Failure
5-10
Secure Hardware Failure
5-11
RX RF
5-12
RX RF Failure
5-13
FGU
5-14
FGU Failure
VCO
5-15
VCO Failure
5-16
GPS
5-17
GPS Failure
5-18
Troubleshooting
Page
No.
5-19
5-20
5-21
5-22
5-23
5-24
5-25
5-26
5-27
5-37
5-38
5-43