I want to start fresh with a post on this tv. For all of you who know your stuff this will be a challenge. I'm wondering if just maybe with some various input from people if maybe we can solve this problem. There are no schematics out there for this tv. It is an older Hitachi plasma.
Voltages I need:
3.3V
5V
75-90V
50-70V
Voltages I have:
3.3V
4.55V
5.96V
1-2V Present where the higher voltages should be.
Turn the power on here the relays click and board energize. About 3-5 Seconds later the board de-energizes and Led goes to constant blinking green. The 3.3V, 4.55, 5.96 come on when the board energizes and remain on after it de-energizes. The higher voltages never appear whereas they did when I first started troubleshooting the tv last year. I soldered jumpers to the 2 main input filter caps. I am getting roughly 7 volts on the filter caps when I first turn the tv on and then thereafter. I also soldered jumpers to the primary side on one of the transformers which I think are for the higher voltages. i see roughly 4.1 Vac. Not even sure if I can use a dmm on a tv transformer. I'm thinking I should be using an O scope. I would like to see if I can force the psu on. One of the connectors from the main board to the psu goes to a pin that goes to the Collector on a transistor on the psu. Is this the pin that gets the ON Signal from the main board? Any other input is much appreciated. Hoping I can get many thoughts on this.
Voltages I need:
3.3V
5V
75-90V
50-70V
Voltages I have:
3.3V
4.55V
5.96V
1-2V Present where the higher voltages should be.
Turn the power on here the relays click and board energize. About 3-5 Seconds later the board de-energizes and Led goes to constant blinking green. The 3.3V, 4.55, 5.96 come on when the board energizes and remain on after it de-energizes. The higher voltages never appear whereas they did when I first started troubleshooting the tv last year. I soldered jumpers to the 2 main input filter caps. I am getting roughly 7 volts on the filter caps when I first turn the tv on and then thereafter. I also soldered jumpers to the primary side on one of the transformers which I think are for the higher voltages. i see roughly 4.1 Vac. Not even sure if I can use a dmm on a tv transformer. I'm thinking I should be using an O scope. I would like to see if I can force the psu on. One of the connectors from the main board to the psu goes to a pin that goes to the Collector on a transistor on the psu. Is this the pin that gets the ON Signal from the main board? Any other input is much appreciated. Hoping I can get many thoughts on this.
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