This WD 62825 had the V26++ chassis Rebuilt By Mitsu 3 years ago. I started off with "THE BLOD" problem. After many hours surfing techlore and other web sites, I ordered the capasitor kit from TVrepair.com and replaced 35 caps. I only found one bulging cap C8780 on the signal board. All caps that I removed were 105C panasonic. I reassembled, only to have the timer/power light flashing fast again. Disassembled elect chassis, checked the only solder joint I made that I questioned, reassembled without the sheilds and connected to the tv so I could check the test points on the power supply board. Now the bootup sequence completes. I push the power sw, power light stays on but lamp never lights and I get error code 12. Some TPs on the power board have the correct voltages but several (ie 3.3 =0 volts 5.0 =.845 Volts) don't. The fuses all ck good continuity while still on the pcb. Fuses f9a09 and f9a07 are not powered and are in the same proximity as the bad test points. I beleive the connector in this area of the power pcb goes to J9 the DMD pcb.
Any advice is greatly apprecited. Barry
F9a09 has to do with fan control, take a good look at C9A77 and C9A78 see if there is power going to them.
Evil thanks for the help. C9A77 and C9A78 don't have power, Sorry for the delay but between work and the honey do list tv comes last
Barry
TP 5V =0.0
TP10V =0.0
TP-15V =-15.5
TP+15V =+15.5
TP 12V =0.0
TP 6VS =7.1 Sorry for the double post but I hit the wrong key
Let's see if F9A03 has power if I'm not mistaken tp12v comes from the 12vs power supply. F9A03 is the start of 12vs supply for the dmd and fan control.
I will try to follow the path from the 12vs to F9A03 and tp12v tomorrow.
C9A09,C9A10 & C9A08 Have slight tan color to rubber coating while C9A11&C9A05 &06 are white.
F9A01 138VDC 140VAC
F9A02 0VDC 0VAC
F9A03 0VDC 0VAC
F9A04 0VDC
F9A05 0VDC
F9A06 12.8VDC
F9A07 0VDC
F9A08 12.8VDC
F9A09 12.8VDC
Also noticed D9A27 getting very warm after 10 minuets D9A26 no heat (both have large heat sink). Thanks again
Barry
F9A03 is the beginning of 12VS which feeds TP12v. So you can supersede the process of tracing it back by going straight to its source being F9A03 which is fed by a transformer. You could spend days weeks or even months tracing paths, or chasing your tail. One thing you could do is send the board in to ptscorp.com and let them trace it for you or give you a reconditioned board in exchange for yours with a little cash to boot. Or you could get it from Mitsubishi themselves which I think are selling them for around 200. The problem is narrowing it down to a single board. Let me check the schematic and see how the transformer is fed, to determine if its the transformer or the power that supplies the transformer from another board. But seeing as how the TP12V is part of the supply for the fan and dmd it should be powering on as soon as the tv is turned on. So the question is are you getting power before or after the transformer.
I see what your saying about the diodes you may have bad windings on the transformer, burnt out.