Hi guy's, have a problem with my home-theater which is really testing my limited knowledge.
If anyone can assist I would really appreciate their help...
Philips HTB5580/98 Home Theater, 18months old.
Problem - Not power up!
Symptoms - Problem started with unit not powering up sometimes, or only staying on for around 2mins. Then turned off with no standby LED.
Got worse, now not power up and no standby LED.
Remove power, replace and standby LED only stays on for around 1 - 2 seconds.
Local AC voltage should be 220v - we only ever get around 200v !
Voltage at main filter capacitors - 280v DC
TNY179PN - replaced with TNY279PN
TOP261EN - replaced
Optocouplers - replaced
Main Filter Capacitors - removed, tested with ESR meter + capacitance meter - tested OK
Secondary Capcitors replaced:
CE516
CE505
CE506
CE507
ZD503 - replaced
Removed both transformers and tested with DMM + Analog, both primary and secondary give very low resistance values.
Don't have an insulation resistance tester.
Visual inspection and tested all components best I can using Digital MM, Analog MM, ESR meter, Capacitance meter.
Don't see any more than 0.6v at any of the output voltages (voltage varies slightly between pins). Should be 34v, 12v, 5v.
Tested voltages with power supply connected to mainboard + amplifier + DVD and standalone and by removing connectors from the other boards one at a time.
Have checked resistance between voltage out pins and ground using analog meter on 1x, get very low readings but can't find aything shorted on each rail.
Any suggestion on what to check next ?
If anyone can assist I would really appreciate their help...
Philips HTB5580/98 Home Theater, 18months old.
Problem - Not power up!
Symptoms - Problem started with unit not powering up sometimes, or only staying on for around 2mins. Then turned off with no standby LED.
Got worse, now not power up and no standby LED.
Remove power, replace and standby LED only stays on for around 1 - 2 seconds.
Local AC voltage should be 220v - we only ever get around 200v !
Voltage at main filter capacitors - 280v DC
TNY179PN - replaced with TNY279PN
TOP261EN - replaced
Optocouplers - replaced
Main Filter Capacitors - removed, tested with ESR meter + capacitance meter - tested OK
Secondary Capcitors replaced:
CE516
CE505
CE506
CE507
ZD503 - replaced
Removed both transformers and tested with DMM + Analog, both primary and secondary give very low resistance values.
Don't have an insulation resistance tester.
Visual inspection and tested all components best I can using Digital MM, Analog MM, ESR meter, Capacitance meter.
Don't see any more than 0.6v at any of the output voltages (voltage varies slightly between pins). Should be 34v, 12v, 5v.
Tested voltages with power supply connected to mainboard + amplifier + DVD and standalone and by removing connectors from the other boards one at a time.
Have checked resistance between voltage out pins and ground using analog meter on 1x, get very low readings but can't find aything shorted on each rail.
Any suggestion on what to check next ?
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