LG 32lc46 totaly dead

[vinceroger69]

Re: LG 32lc46 totaly dead

The 1k resistor from 5Vstby to PS_ON test is to verify if the power supply is OK, which from your reports, the power supply is OK. Now you need to find out whay you are not getting the 3.3~5VDC from the main board to feed the PS_ON pin on the power supply.
Time to check the voltage regulators in the main board next.

just posted some pics up not very good though will get better tomorow dont know if you can see voltage regs to point out to me?
this is the exact board
http://www.sendz.co.uk/lg-42lf65-zc-...n-av-405-p.asp

[vinceroger69]

Re: LG 32lc46 totaly dead

another question even with this new power supply in connected up i am still not getting any leds lit when tv is plugged in is this normal? or is this because i am not getting the 3.3~5VDC from the main board to feed the PS_ON pin on the power supply

[Jasgriff]

Re: LG 32lc46 totaly dead

another question even with this new power supply in connected up i am still not getting any leds lit when tv is plugged in is this normal? or is this because i am not getting the 3.3~5VDC from the main board to feed the PS_ON pin on the power supply

The LED's on the tv will be power from the mainboard. So you should have voltage going to the mainboard which should power up the LED and send an on signal back to the power supply to turn it on.

[budm]

Re: LG 32lc46 totaly dead

That is not normal, since the standby power supply is always on to run the micro controller, the 12v/24v power supplies are switched on when power switch is activated.
So when you hit the power switch, nothing happens?

[vinceroger69]

Re: LG 32lc46 totaly dead

no nothing both the 5 volts on the psu have 5 volts checked them twice now also on the very bottom of the main board it has 1 connector i have just tested the point on the board thats stamped 5 volts its there when the sets plugged in following this wire back it goes to the led borard on the bottom of the set and then by wires up to the power momentery switch board.
just looked at the connection on the bottom of the main board they say
led r
led g
stby 5v this i have when sets plugged in
gnd
ir
gnd
key2
key1
so not sure whats going on here

[Jasgriff]

Re: LG 32lc46 totaly dead

Have you tried pointing your remote at it and pressing some buttons to see if the light flashes?

[Jasgriff]

Re: LG 32lc46 totaly dead

The best way of seeing whats going on with your mainboard is to check the voltage regulators like Budm asked. The picture is not clear enough for us to really tell you where they are so if you take a look at the picture below. I think yours will look like this. Can you find them and let us know the numbers off them please.

[vinceroger69]

Re: LG 32lc46 totaly dead

on the front of the board 2 x sc156515m 2x kia78r05f all 5 pins on each all of these are by the top sockets by where the psu to main board plugs go
2x kia 78r3ff by the tuner both 5 legs
and have tried pressing remote no light from led att all will try to get pics tomorrow miday for you will try to take four of each side

[Jasgriff]

Re: LG 32lc46 totaly dead

Ok these Voltage regulators supply the board with the different voltages that each different component needs. What we need to do is ensure that they all have power and they they are outputting the correct voltages for the circuits to work correctly.

Below is the spec sheet for the first number you provided. What we need you to do is to tell us what voltage you are getting on each of the pins. You can use the metal tab at the top of the regulator to put your black probe and then test each of the pins with your red probe.

sc156515m
http://pdf1.alldatasheet.com/datashe...CH/SC1565.html

[vinceroger69]

Re: LG 32lc46 totaly dead

will do this tomorrow after i have taken pics and put board back in for testing cheers guys

[Jasgriff]

Re: LG 32lc46 totaly dead

Ok do the same with the other regulators and then post your findings on here that might help work out what's going on.

[vinceroger69]

Re: LG 32lc46 totaly dead

some pics will check voltages in a min
well some voltage tests done still no red or green led on the front tried remote as well no flashes nothing
all these regs have five pins i tested left to right
ic 505 by the tuner KIA 78R33F
pin 1 o volts
pin 2 1.08 volts
pin 3 o volts
pin 4 o volts
pin 5 o volts
1c903 SC158515M
pin 1 3.29 volts
pin 2 3.29 volts
pin 3 0 volts
pin 4 1.18 volts
pin 5 0.79 volts
1c 902 AEH14A 731J28
3 pin device
pin 1 0 volts
pin 2 o volts
pin 3 4.69 volts
all the other regs on the board 0 volts to all pns

[Jasgriff]

Re: LG 32lc46 totaly dead

Ok here is the Spec sheet for the KIA78R33F

http://www.alldatasheet.com/view.jsp?Searchword=78R33F

SC158515M I cant find this part number? is this correct was this writing all on one line?

AEH14A 731J28 cant seem to find this one either?

Can you retest the KIA78R33F using pin 5 as ground and tell us what you get.

[vinceroger69]

Re: LG 32lc46 totaly dead

Ok here is the Spec sheet for the KIA78R33F

http://www.alldatasheet.com/view.jsp?Searchword=78R33F

SC158515M I cant find this part number? is this correct was this writing all on one line?

AEH14A 731J28 cant seem to find this one either?

Can you retest the KIA78R33F using pin 5 as ground and tell us what you get.

just retested KIA78R33F
pin 1 0 volts pin 2 0.86volts pin 3 0 volts pin 4 0 volts

sorry 1c 903 should be sc156515m
the one you sent the data sheet for already
1c902 is a EH14A 731J28
pin 1 0 volts
pin 2 0 volts
pin 3 4.69 volts

[vinceroger69]

Re: LG 32lc46 totaly dead

just saw this on ebay it says it for a 42 inch plasma although all the board part numbers match up 100% would this work as mines a 32 inch lcd?
http://www.ebay.co.uk/itm/2510195867...84.m1438.l2649

[sabre504]

Re: LG 32lc46 totaly dead

I know that the samsungs can be changed in the service menu to tell the board what screen size to run but am not sure if the same can be done with this model .
I am sure one of the more experienced posters will be able to tell you but have found a service manual which i have attached

[sabre504]

Re: LG 32lc46 totaly dead

Cant get it to upload will mail it to you

[vinceroger69]

Re: LG 32lc46 totaly dead

cheers much appreciated

[tom66]

Re: LG 32lc46 totaly dead

The only problem you might have is the 32" LCD is 1366x768, but most older LG plasma displays are 1024x768. It might be good enough to enter a service menu, though.

Enter the service menu by pressing MENU on the TV at the same time as MENU on the remote.

[vinceroger69]

Re: LG 32lc46 totaly dead

cheers tom not brought it yet still cant get set running new power supply all correct voltages when linked 5volt stby and ps on with 1 k resistor every voltage spot on remove link put all connectors back on power supply set dead no leds nothing.so persume its a main board fault? i have just been emailed the service manual with the circuit in but how can i upload the pages from it for you guys to help me fault find voltages on the main board? as could be a voltage reg issue on the main board tell me what to test i will but follow a circuit diagram thats another issue!