Current condition: Will not power up. No LED indication at all. A slight chirp is heard when plugged in. Moments after being unplugged, another chirp is heard (dissipation).
Considering the amount of information regarding the DM fix, I of course pursued that immediately. I replaced all seven 1000uf capacitors and checked the fuses within the DM. No obvious damage there, and I replaced them completely based on the fact that this is a known issue.
Additionally, I have checked all the Standby voltages of 12vdc, 28vdc, 6vdc, and 32vdc. All of these voltages are present when plugged in. I also measured at the cable going to the DM and verified the 12v, and 28v are there at the PF cable.
The situation happened while I was watching the set for several hours. I attempted to change inputs from my DVR to my cable and the TV changed to no picture with the LED still on. There seemed to be no response from the remote, so I powered it down. It has not powered back up since.
I have unplugged the unit overnight to make sure it was dissipated. I have attempted the reset. I have attempted the DEVICE+MENU to attempt an Error Code. The LED will not show any indication.
I am the only owner of this set as well, and have had it since it was built in 2003. I have had some hiccups where it would not turn on, but a power cycle, or a reset resolved it. Not this time.
I am not a television repair tech, though I did repair CRT monitors about 18 years ago. I would appreciate any insight on this television! I see so much chatter on this site about it, and Mitsubishi in general, I would appreciate your help! I only have a basic multimeter at my disposal and the means to solder and replace components.
I also noticed tonight, that the DM when connected to the POWER PCB, has a blinking diode on the board D5401. It is located near the upgrade slot.
This diode blinks a few times whenever AC power is plugged in. I recreated this several times while connecting each of the plugs coming out of the DM.
The DM does not blink when the DA connector is fastened. This is the only time the diode does not blink when AC is applied.
Possible load on that circuit?
Still no LED on the front of the set at any time.
Additionally tonight, I remembered how the horizontal circuit, or the flyback could load down the system to keep a monitor from powering up. I removed the flyback transistor to see if this would start up the computer, or show an attempt to power up. The LED on the front still shows no sign of life.
I feel like I am overlooking something that should be obvious to me, but I cannot think of anything, or remember the course of troubleshooting this type of issue.
there is probably a lot of info on this ste and condition, using the site search engine w/your model #, but you could try
Pulling the DM board again, while you have the chassis slid out look at the wiring connectors to the rear that might have come stretched and unplugged, unplug then reseat any connectors you suspect, check for wiring that pulled loose and is under the chassis.
Remove the dm shield, recheck your work, reinsert dm without shield, then install shield.
If that dosen't fix it, pull the whole chassis and look for coolant leaks and bad solder before you start checking voltages.
This just happened to me on Monday. Came home and the TV would not power on, the timer light was blinking. Unplugged several times, same thing, reset several times, same thing. Had a tech come over today (from Andersons TV where I bought it) and he charged me $99.95 to tell me that the DM box was dead, would cost $790 to replace, however they don't have/support it anymore so I have a $4k bookend. Any ideas or suggestions would be most appreciated.
Did you find this link? Seems Larry has the answer.
http://www.techlore.com/forum/thread/19174/Green-Blinking-Light-on-Mitsu...
look at previous pages for all those he helped
Cheers
I explained in detail that this is not the blinking light issue. That was the first thing I did to the set, knowing it was a common issue. There is no light at all. No blinking light, no indication of the DM issue. All standby voltages are present at the DM.
Acoording to Mitsubishi's V23 training manual, it is recommended to replace the IC9A10 Standby Regulator based on the chirp made by the TV.
I have ordered this part online for $13, and it is on the way to my home. Hoping this does the trick, but I have no way of testing the part prior.
The chirp explained at the top in detail was not a symptom. Apparently this set will chirp with AC power applied, and chirp again to discharge when AC is removed. This is normal power supply actions. (just disregard it)
The resolve for this issue was actually disconnecting the the front control board. I left the front input connected, however by disconnecting the control board you must use a remote control to power up the tv and change inputs, etc. You will also no longer get a power light to indicate it is on.
Not sure if the failure is the board on the front, or the controller that the wires go to, however using a remote is just fine for me.