e550vl turns on 24v going to inverters fluctuates

[budm]

Re: e550vl turns on 24v going to inverters fluctuates

Some measurement still does not make sense since the boosted voltage went down from 400v to 160v, the 400v is used for driving that main transformer that produces the 12v, 18v, and 24v. I expect that to affect all the voltage reading.
Do try using lamps as I suggested earlier and monitor that PS_ON signal. I expect the over current condition to shutdown the main power transformer driving circuits but not the PFC.
Put the lamp on the 12V line also.

[kornwood]

Re: e550vl turns on 24v going to inverters fluctuates

I replaced the 4 caps on the inerters and now I get a steady 24v but no blon voltage
a has 1.1 and theres no b and c is
ah so I had the 18v cable unplugged when I plugged it in I lost 24v but have voltage on blon so leafs me to something wrong on mainboard

[kornwood]

Re: e550vl turns on 24v going to inverters fluctuates

inverter boards came in today and didnt fix my issue

[budm]

Re: e550vl turns on 24v going to inverters fluctuates

The BL_ON is generated by the main board and it is routed through the power supply connectors (the power supply board is used as the junction point for the BL_ON and the Dimming control signals), I do not remember if the A or B , or C is the BL_ON signal. At this point we need to find out why the BL_ON is not present.

[kornwood]

Re: e550vl turns on 24v going to inverters fluctuates

i now get 1.8v on a and 1.0v on c now going all the way to the master inverter

[kornwood]

Re: e550vl turns on 24v going to inverters fluctuates

shouldnt c which goes to on\off on inverter be atleast 2.5v-3.3v instead of the 1.ishv i get

[budm]

Re: e550vl turns on 24v going to inverters fluctuates

If you trace out the conection from the Inverter board BL_ON pin, which pin is it connected to on the Power supply board, A, B, or C. I do expect it to be >2.5V. We can look up the spec sheet of the LCD panel, it will tell all the pinouts and voltages.

[kornwood]

Re: e550vl turns on 24v going to inverters fluctuates

its pin c
could i cut the wire and connect it to the pson to test so it gets 2.8v

[budm]

Re: e550vl turns on 24v going to inverters fluctuates

Yes you can cut just that line then use a 1K resistor between that BL_ON pin on the inverter board and the 5V standby to force the backlights to turn on. When you turn on the TV, the 24v should come on, same for the backlights.

[kornwood]

Re: e550vl turns on 24v going to inverters fluctuates

can I make that connection prmanant cause tv worked

[kornwood]

Re: e550vl turns on 24v going to inverters fluctuates

ok hdmi dont work will try others well everything else works hdmi 1 and side hdmi dont work but #2 does

well #2 will show roku boot up on 2 then disapears wont show anything from ps3 so no hdmi works sound does
but all other does will try tuner next

[budm]

Re: e550vl turns on 24v going to inverters fluctuates

The BL_ON should be applied after the PS_ON is applied to turn the power supply since you want the 12v/24v to be stable first before turning on the inverter which is very heavy load. So BL_ON should have slight delayed after the PS_ON is present.

[kornwood]

Re: e550vl turns on 24v going to inverters fluctuates

ok so a toggle switch would work then mounted outside
its currently using the resistor

[budm]

Re: e550vl turns on 24v going to inverters fluctuates

That will work too, just put the switch in series with the resistor.

[kornwood]

Re: e550vl turns on 24v going to inverters fluctuates

would the hdmi issue have something to do with why the blon voltage is low but it will work fine for me with out them ill just use the component cables for hd thanks again

[budm]

Re: e550vl turns on 24v going to inverters fluctuates

The main board seems to have multiple problems, it is not processing the signals correctly.
There are many I/O signals and interfaces for the micro controller and the related supporting to process all those signals.
I believe that the main board may die soon.