Hello, good day everyone,
I'm trying to fix this video projector and I'm not having any luck. If anyone has any suggestions, I would be very grateful.
The problem is that it won't turn on. I've been investigating and testing for several days.
The startup process fails. When I plug it into the power outlet and it's in standby mode, pressing the power button makes it try to start. The solid red standby LED changes to flashing green, and I can hear a fan running inside the optical unit. But after about a minute, the startup attempt stops, and the standby LED starts flashing red six times repeatedly, which, according to the manual, indicates that the main CPU has failed to start.
IMPORTANT NOTE: When I was initially testing it without disassembling it, I noticed that it sometimes started up, and when it was running, it even worked perfectly for hours at a time. But when I turned it off and on again,
many times it wouldn't start.
The times it did start, I noticed that while in standby mode, the HDMI inputs initially showed a +5V voltage.
However, the times it didn't show any voltage while in standby mode were when it wouldn't start.
From this, I've tried to locate this +5V voltage internally, but it's quite laborious.
I still haven't located where this voltage is generated. The main power supply only generates the voltages
3.3V, 12V, 15V, and 16.7V (apart from the ballast board for the projector).
The 5V voltage is necessarily generated on the main motherboard. There, I've seen quite a few voltage reduction converters
more than I expected. I tried supplying +5V from an external power source to the USB ports,
but it doesn't go beyond that point. I can't apply voltage to the HDMI ports because they're powered by the HDMI input selector chip itself, and doing so could damage it. I also can't figure out which pins supply the 5V to this HDMI selector chip; I only have a pinout, not the datasheet. It seems that this +5V supply is failing more generally across the main board, but I haven't been able to find where it's generated, which is the down converter, or if a main control chip needs to send an enable command.
FINAL CONCLUSION
What I do know is that this +5V should be present in standby mode, and many large components and main chips shouldn't be active in this state.
Where can I go from here? If this projector hadn't worked at all, I would have thought it was dead, or that one of the large "BGA" chips soldered underneath was faulty.
Could you provide the exact Sony projector model number and, if possible, the chassis/main board part number printed on the PCB?
Sony VLP PHZ50 Board 4H.4YJ01.A00
When the projector is in the “bad” standby state with no HDMI +5V, what voltages do you measure on the main board regulators/test points, especially any 5V, 3.3V standby, enable pins, and whether any regulator output is shorted to ground?
3.3V, 12V, 15V, 16.7V
I'm trying to fix this video projector and I'm not having any luck. If anyone has any suggestions, I would be very grateful.
The problem is that it won't turn on. I've been investigating and testing for several days.
The startup process fails. When I plug it into the power outlet and it's in standby mode, pressing the power button makes it try to start. The solid red standby LED changes to flashing green, and I can hear a fan running inside the optical unit. But after about a minute, the startup attempt stops, and the standby LED starts flashing red six times repeatedly, which, according to the manual, indicates that the main CPU has failed to start.
IMPORTANT NOTE: When I was initially testing it without disassembling it, I noticed that it sometimes started up, and when it was running, it even worked perfectly for hours at a time. But when I turned it off and on again,
many times it wouldn't start.
The times it did start, I noticed that while in standby mode, the HDMI inputs initially showed a +5V voltage.
However, the times it didn't show any voltage while in standby mode were when it wouldn't start.
From this, I've tried to locate this +5V voltage internally, but it's quite laborious.
I still haven't located where this voltage is generated. The main power supply only generates the voltages
3.3V, 12V, 15V, and 16.7V (apart from the ballast board for the projector).
The 5V voltage is necessarily generated on the main motherboard. There, I've seen quite a few voltage reduction converters
more than I expected. I tried supplying +5V from an external power source to the USB ports,
but it doesn't go beyond that point. I can't apply voltage to the HDMI ports because they're powered by the HDMI input selector chip itself, and doing so could damage it. I also can't figure out which pins supply the 5V to this HDMI selector chip; I only have a pinout, not the datasheet. It seems that this +5V supply is failing more generally across the main board, but I haven't been able to find where it's generated, which is the down converter, or if a main control chip needs to send an enable command.
FINAL CONCLUSION
What I do know is that this +5V should be present in standby mode, and many large components and main chips shouldn't be active in this state.
Where can I go from here? If this projector hadn't worked at all, I would have thought it was dead, or that one of the large "BGA" chips soldered underneath was faulty.
Could you provide the exact Sony projector model number and, if possible, the chassis/main board part number printed on the PCB?
Sony VLP PHZ50 Board 4H.4YJ01.A00
When the projector is in the “bad” standby state with no HDMI +5V, what voltages do you measure on the main board regulators/test points, especially any 5V, 3.3V standby, enable pins, and whether any regulator output is shorted to ground?
3.3V, 12V, 15V, 16.7V
