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Post by mastertech on Feb 17, 2017 21:36:08 GMT -5
Yes.
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nashou
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Post by nashou on Feb 17, 2017 21:38:17 GMT -5
Ok, go back and check voltages at pins 2 and 3 of ic901. 1.16 and 1.024 respectively And just noticed parts of the screen are lit up a little jibberish  |
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Post by mastertech on Feb 17, 2017 21:44:34 GMT -5
Ok, those voltages are close enough. And it might not be going into protect mode now.
So now for some more voltage testing to see why that was being turned on. IC77 pins 20, 27, 28. test voltages.
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nashou
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Post by nashou on Feb 17, 2017 21:59:06 GMT -5
Ok, those voltages are close enough. And it might not be going into protect mode now. So now for some more voltage testing to see why that was being turned on. IC77 pins 20, 27, 28. test voltages. 5.5 2.8 3.3 they look good except pin 27 a little low |
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Post by mastertech on Feb 17, 2017 22:03:18 GMT -5
Now ic73, pins 28 and 6
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nashou
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Post by nashou on Feb 17, 2017 22:13:03 GMT -5
28 had 20mV
6 had 1.29
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Post by mastertech on Feb 17, 2017 22:16:19 GMT -5
Yep. We are getting close. Locate 2 ic's, IC71 and IC75. Both larger ic's. Turn on receiver and see if either one is getting hot.
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nashou
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Post by nashou on Feb 17, 2017 22:22:55 GMT -5
Receiver been on since we removed the transistor , those two chips are not hot, just warm .
About 28c
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Post by mastertech on Feb 17, 2017 22:25:03 GMT -5
I was looking at schematic and your 800 may not have ic75. Does your unit have 2 HDMI outs?
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nashou
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Post by nashou on Feb 17, 2017 22:27:25 GMT -5
I was looking at schematic and your 800 may not have ic75. Does your unit have 2 HDMI outs? Yes I have ic75 and two outs |
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Post by mastertech on Feb 17, 2017 22:31:08 GMT -5
Ok. Back to IC73 and check pin 20 for 5.5v and pin 27 for 3.3v
If they are around this then remove L713 and see if pin 6 of ic73 comes up to 3.3v
Pin 27 may only be 2.8v but that is ok.
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nashou
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Post by nashou on Feb 17, 2017 22:55:43 GMT -5
No go. No voltage on pin6 now.
But on one side of L713's pad has 1.3 volts
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Post by mastertech on Feb 17, 2017 23:07:34 GMT -5
So on ic73 pin 20 you have 5.5v and pin 27 you have app 3.3v?
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nashou
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Post by nashou on Feb 17, 2017 23:11:49 GMT -5
So on ic73 pin 20 you have 5.5v and pin 27 you have app 3.3v? Yes , 5.5 and 2.85 pin 28 has no voltage for added informational purpose |
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Post by mastertech on Feb 17, 2017 23:17:10 GMT -5
Looks like at least ic73 is bad. It could be a shorted cap (C732 or C735). Do a diode test across both these caps to see if you get a short.
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