Mitsubishi LT-46149 error code 41

[bartstop]

The red power led is glowing solid but tv won't turn on. The service manual says "3.3VS or 5VS STANDBY-SHORT" when I put it in to diagnostics mode.

Here are the voltage readings:

Main Board to Power Supply
DIMMING - 0V
BACKLIGHT ON OFF - 0V
INV SHORT - 3V
INV RELAY - 0V
PANEL PWR - 0V
GND - 0V
PNL 12 SHORT - 0V
AC OFF - 0V
MAIN RELAY - 0V


Power supply to main board
21 VA - 0V
21 VA - 0V
A GND - 0V
A GND - 0V
PANEL VCC - 0V
PANEL VCC - 0V
GND - 0V
GND - 0V
12 VSL - 12V
12 VSL - 12V
12 VSL - 12V
GND - 0V
GND - 0V
GND - 0V

When I first plug it in, I can hear a relay clicking on then back off a second or two later. If I unplug the cable going from the main board to the sound board the relay stays on and "MAIN RELAY" is 3v but the tv still won't turn on. For some reason that sound board is making making the main relay shut off.

Now here's the weird part. I was checking voltages and all the sudden the backlight turns on. I stand the tv up and I have a blue screen. So, I push the power button and the screen goes black then a Mitsubishi Logo comes on the screen for about 2 seconds. Then the main relay kicks back off. That's happened twice and I can't reproduce it. The second time I wasn't doing anything.

Does anybody know which pins are supposed to be standby voltage?

[nomoresonys]

Re: Mitsubishi LT-46149 error code 41

Look the powerboard over, on under side, check for cold, bad/cracked solder joints, example: https://www.youtube.com/watch?v=XhlNewlhH3U

[bartstop]

Re: Mitsubishi LT-46149 error code 41

Look the powerboard over, on under side, check for cold, bad/cracked solder joints, example: https://www.youtube.com/watch?v=XhlNewlhH3U

I re-flowed every one that looked even slightly suspicious. Didn't help.

When I disconnect the sound board from the main board. It gives me code 12 which is "normal off" "no problem detected".

I ordered a refurb main board. Hope that fixes it.

[R_J]

Re: Mitsubishi LT-46149 error code 41

Just a note on the 21VA being 0, that is normal as there are no components for that supply ie D9A31, C8a39 etc. are not populated onthe board.