Emerson LF461EM4 Dead set

[tech2014]

I get no standby LED. I notice that when I test the voltages, I got 160V across the main filter caps. I found that when I remove the main board connector I got following DC voltages.

ALL 3.3V -3.3V
P-ON_h2- 0V
P-ON +21V-11.54
Amp +13V-6.6V

I lose them when I install the main board ribbon cable. Is this a main board issue? Can I force the p/s on to get voltages or does this one not need a force on. I have never worked on an Emerson Tv before.

See link below for the parts for this tv.
https://www.shopjimmy.com/emerson-a3...upply-unit.htm
https://www.shopjimmy.com/emerson-a3...lf461em4-a.htm

[tech2014]

Re: Emerson LF461EM4 Dead set

UPDATE!!!


I tested the P-ON+21V line on the main board and it measures 27.6 ohms. On the power board, it reads very high resistance. I guess there is a short somewhere on the main board.

[budm]

Re: Emerson LF461EM4 Dead set

ALL 3.3V -3.3V
P-ON_h2- 0V
P-ON +21V-11.54
Amp +13V-6.6V
Those two Voltages are correct when TV is in standby mode, when P-ON H2 is high then those Voltages will go up as noted.

[tech2014]

Re: Emerson LF461EM4 Dead set

Thanks Budm. 3 parts are shorted on the main board. The EEPROM and 2 other ICs. SJ has a repair kit for it. I also ordered the kit for the p/s just in case. They are common p/s parts so I could use them anyways.

[garryls tv]

Re: Emerson LF461EM4 Dead set

check c3214 cap shorts on main bd pulls down power supply sometimes makes it squeal

[GAStuntman]

Re: Emerson LF461EM4 Dead set

Hello All,
I have this same TV. When plugged in, no standby light and set will not power on. There is a pulsed squeal that I think is coming from the T601 transformer. The squeal pitch changes after a few minutes of having the set plugged in.

Voltages at the PS connector:
Pin 8: 3.28V
Pins 15-18: 6.3V
Pins 20-23: 11.5V

Same connector at the main board:
Pin 8: 0.9V
Pins 15-18: 1.5V
Pins 20-23 -4.1mV~500mV

Any help is greatly appreciated...

[R_J]

Re: Emerson LF461EM4 Dead set

I wonder if post #5 is any help, did you check that cap?

[freakaftr8]

Re: Emerson LF461EM4 Dead set

Also check the four SMD caps on back side of mainboard under the audio amp IC.. one of these shortred on me loading down 3.3v.

Audio amp IC is under the metal shield.

[dskall]

Re: Emerson LF461EM4 Dead set

I picked up this tv dead with chirping noise. Unplugging power to main cable got rid of chirping. Thanks to garryls tv was shorted c3214 smd cap upper left corner of main next to black 330 coil. Cleared the short but still dead. Further checking and found 5.4vdc on 3.3vdc. Noticed someone had replaced 3.3 reg. to 5vdc. Suspected corrupted eeprom. Tv powered up and in short testing is working. Only thing concerns me is slight buzzing from power supply. Similar to buzzing from plasma. Never noticed any buzzing from lcd's. Guess I will have to do some long term testing before I get rid of it.