Test & Debug Flow - Zenith XBV323 Series Service Manual

2. Test & debug flow
TEST
Check the
AC Vol tage
Power PCBA (110V
or 220V)
Yes
Switch on the Power PCBA
Is
the DC Voltage
outputs OK?
(5V, 3.3V, 8V, 12V)
Yes
Is 3.3V and 2.5V DC
outputs normal on main
PCBA?
Yes
Communication between
VCR & DVD is normally?
Yes
Connect to PC RS232 Cable and
update the FLASH memory code.
Update
FLASH(IC5A1)
successfully?
Yes
A
No
Check the POWER PART
No
Check the POWER PART
No
Check the regulators or diode(D601).
No
Check the cable connection.
(PDV02)
1. Check 27MHz system clock.
2. Check systemreset circuit.
No
3. Check FLASH R/Wenable signal PRD,
RWR.
4. Check RS232 SIGNALS.
5. Check FLASH Memory related circui t.
Replace FLASH( IC5A1)
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