System Test Flow - JVC XV-N350B Service Manual

ELECTRICAL TROUBLESHOOTING GUIDE

3. SYSTEM TEST FLOW

TEST
Check the AC
Voltage Power PCBA (110V
or 220V)
Switch on the power PCBA
Is the DC
voltage outputs OK?
(5V, 3.3V, 12V, 5.6V
MOTOR)
Make sure the main PCBA don't
short on VCCs and switch it on.
Is 3.3V
and 1.8V DC outputs normal
on main PCBA?
Connect to PC RS232 cable and
update the FLASH memory code.
Update FLASH
successfully?
A
YES
YES
YES
YES
YES
NO
Replace power PCBA or AC transformer.
NO
Repair or Replace power PCBA
NO
Check the regulators or related diodes.
1. Check 27MHz system clock.
2. Check system reset circuit.
NO
3. Check FLASH R/W enable signal PRD,
RWR.
4. Check RS232 SIGNALS.
5. Check FLASH Memory related circuit.
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