Zenith DVB611, Service Manual

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3-4
3. Test & debug flow
TEST
Check the AC Voltage
Power PCBA(110V or 220V)
YES
Switch on the Power PCBA
YES
Is the DC Voltage outputs OK?
(5V, 3.3V, 12V, 5.6V MOTOR)
YES
Make sure the main PCBA don't short on
VCCs and switch it on.
YES
Is 3.3V outputs normal on main PCBA?
YES
Connect to PC RS232 Cable and update
the FLASH memory code.
YES
Update FLASH successfully?
YES
A
Replace power PCBA or AC transformer.
NO
Repair or Replace Power PCBA
NO
Check the regulators or related diodes.
NO
Is 1.8V Voltage normal for Zoran IC
YES
1. Check Q203. 2. Check D201.
3. Check IC102
NO
1. Check 27MHz system clock.
2. Check system reset circuit.
3. Check FLASH R/W enable signal
PRD,RWR.
4. Check RS232 SIGNALS.
5. Check FLASH Memory related circuit.
NO