TV Powers on, then Off - Emerson LF501EM5F

[Shyguy707]

First off, yes I have seen the sticky for general troubleshooting as well as previous guides on this exact model, I actually followed one of them to get me to this point as my PSU was doing the chirping sound due to a malfunctioning C3214 capacitor.

Now my T.V. actually turns on. As soon as I plug in the power cable into AC power (without touching power switch on T.V.), the screen will illuminate for a few seconds, then shut off. I press the power switch and the T.V. will do the same thing, refusing to stay on.

I'm getting closer, but I need more help to get there, I would love to get this curbisde find up and running for my workshop!

[nomoresonys]

Re: TV Powers on, then Off - Emerson LF501EM5F

Test the voltages at the connector on the powerboard with EVERYTHING hooked up, it's the connector that the cable from powerboard to mainboard hooks into, most times there's a legend/map nearby that gives the expected voltages, you measure them with your mutimeter, set meter to 20 vdc then report them, put neg probe on chassis metal ground, pos probe on pin of connector, measure in standby take note, leave probes where they are then power on tv and again take note of voltages, report them here, example pin 1-ps-on-0 volts standby-power on-3.3 volts.

[nomoresonys]

Re: TV Powers on, then Off - Emerson LF501EM5F

Can you post some focused straight on pictures of each board and one of the whole back, as to see how everything is connected?

[nomoresonys]

Re: TV Powers on, then Off - Emerson LF501EM5F

Could be one or more additional bad caps.

[nomoresonys]

Re: TV Powers on, then Off - Emerson LF501EM5F

Is your version DS1? can tell by looking on back cover, should be close to the model number.

[Shyguy707]

Re: TV Powers on, then Off - Emerson LF501EM5F

See photos, according to serial number prefix, it may be a DS1.

Here are the readings I've got, sorry if the layout is poor:
Stand By Readings
P1: 14.31V
P2: 14.31V
P3: 14.31V
P4: 14.31V
P5: 7.93V
P6: 7.93V
P7: 7.93V
P8: 7.93V
P9: 0mV
P10: 0mV
P11: 0mV
P12: 0mV
P13: 0mV
P14: 3.315V
P15: 0mV
P16: 0mV
P17: 3.315V
P18: 0mV
P19: 0mV
P20: 0mV
P21: 3.315V
P22: 0mV
P23: 0mV

Power-On Readings

P1: 22.68V
P2: 22.68V
P3: 22.68V
P4: 22.68V
P5: 13.02V
P6: 13.02V
P7: 13.02V
P8: 13.02V
P9: 0mV
P10: 0mV
P11: 0mV
P12: 0mV
P13: 0mV
P14: 0mV
P15: 3.314V
P16: 3.05V
P17: 3.3V
P18: 3.0V
P19: 3.10V
P20: 3.2V
P21: 3.314V
P22: 424.8mV
P23: 0mV

[Shyguy707]

Re: TV Powers on, then Off - Emerson LF501EM5F

By the way, forgot to say thanks for the help, bud!

[nomoresonys]

Re: TV Powers on, then Off - Emerson LF501EM5F

It's harder when the pins are not labeled, this board doesn't seem to have a label/legend, try heating with a hairdryer or cooling with freeze-spray or inverted can of air IC3006 on mainboard not powerboard, then plug tv in and see if it starts up or acts any differently.