Motorola APX 7000 Detailed Service Manual page 112

5-8
Power-Up Failure – Low VBUS1 Voltage
Low VBUS1 Voltage
Measure
VCC_SW_5 at
R6544
5.1 < V < 5.6?
Yes
Measure VBUS1
Supply Volatge at
R6521
5.1 < V < 5.6?
Yes
Inspect Supporting
Circuitry for the
Gate of Q6502
Are Parts Solder
Connections and
Placement Correct
Repair Incorrect
Part/s
Proceed to Low
No
SW5 Volatge Flow
Chart
Inspect Q6505 and
No
Supporting
Circuitry
Yes
Check Placement
of Q6502
No
Troubleshooting Charts: Power-Up Failure
Are Parts Solder
No
Connections and
Placement Correct
Yes
Replace VOCON
Board
No
Is Part Placed
Correctly
Yes
Replace VOCON
Repair Incorrect
Part/s
Replace Part