Funai (Emerson) LF501EM4F not turning on

[budm]

Re: Funai (Emerson) LF501EM4F not turning on

Somehow you will need to find out if that 3.3V gets all the way to those pull-up resistors or not.

[jayjoesph]

Re: Funai (Emerson) LF501EM4F not turning on

Somehow you will need to find out if that 3.3V gets all the way to those pull-up resistors or not.

Thats gonna be fun I see them no where after searching zoomed in

[dick_barton]

Re: Funai (Emerson) LF501EM4F not turning on

The resistor should be on the mainboard and possibly close to IC3005

[jayjoesph]

Re: Funai (Emerson) LF501EM4F not turning on

The resistor should be on the mainboard and possibly close to IC3005

Let me know if you see it i looked for least a hour top and bottem pictures and board itself

[dick_barton]

Re: Funai (Emerson) LF501EM4F not turning on

I only have the power supply board layout but not the mainboard layout so unfortunately I cannot help to locate it.

[jayjoesph]

Re: Funai (Emerson) LF501EM4F not turning on

I only have the power supply board layout but not the mainboard layout so unfortunately I cannot help to locate it.

well its BA31T0G0 201 3 If you can or anybody else can help out

[budm]

Re: Funai (Emerson) LF501EM4F not turning on

OK, I just look through the service manual, there are two schematics for the main board, one is type 'A' and the Micro Controller is IC3005 (R8A05011BG-U0). The type 'B has IC3001 (MSD8200DS-S1) as the micro controller. The way PROTECT3 is connected is not the same for the two versions.
So you need to find out which version you have by looking for IC 3005 (for 'A'), or if it has IC 3001 for 'B' version.

[jayjoesph]

Re: Funai (Emerson) LF501EM4F not turning on

OK, I just look through the service manual, there are two schematics for the main board, one is type 'A' and the Micro Controller is IC3005 (R8A05011BG-U0). The type 'B has IC3001 (MSD8200DS-S1) as the micro controller. The way PROTECT3 is connected is not the same for the two versions.
So you need to find out which version you have by looking for IC 3005 (for 'A'), or if it has IC 3001 for 'B' version.

okay mine says MSD8200DS-S1 and is a IC 3001 on the board

[jayjoesph]

Re: Funai (Emerson) LF501EM4F not turning on

Would R3193 be the correct place to check? I read 3.2vdc on one side nothing or jumps to -0.000

[dick_barton]

Re: Funai (Emerson) LF501EM4F not turning on

Can you confirm that with all the jumpers in place and the mainboard disconnected all the leds are powering on and the led voltages at the connector are identical. I think you said 78V in an earlier post.

From what I can make out the 3.3V which should be measured at the Fault inputs to the Led Drivers (pin7) comes via R3189 in series with R3917, both 33K resistors, when Q3103 is not switched on.

When any of the led driver are in Fault condition the corresponding 1K resistor at pin 7 is connected to ground though the IC's internal mosfet. Since these resistors are in series with R3917, this causes Q3013 to switch on.
This will be the case for any of the led drivers should a Fault condition be activated.

When Q3013 is switched on because of a Fault condition this results in the 3.2V you read across R3193

[jayjoesph]

Re: Funai (Emerson) LF501EM4F not turning on

led connecor volatge is 0.75vdc/76vdc/0.74vdc/77vdc/1.2vdc<-(jumped up-down somewhat) 47vdc

You did catch that R1108 R1208 and R1308 were removed correct?

[dick_barton]

Re: Funai (Emerson) LF501EM4F not turning on

Shouldn't there be 3 sets of reading for Led1,2 &3 output?

Edit,
Reading yor reply again I see there are 3 sets of readings.

Which led set is jumping up to 47V ?

[jayjoesph]

Re: Funai (Emerson) LF501EM4F not turning on

Shouldn't there be 3 sets of reading for Led1,2 &3 output?

there is
0.75vdc/76vdc
0.74vdc/77vdc
1.2vdc/47vdc

[jayjoesph]

Re: Funai (Emerson) LF501EM4F not turning on

Shouldn't there be 3 sets of reading for Led1,2 &3 output?

Edit,
Reading yor reply again I see there are 3 sets of readings.

Which led set is jumping up to 47V ?

Sorry i should have worded that more clearly. the 1.2vcd is what was unstable of vled1

[jayjoesph]

Re: Funai (Emerson) LF501EM4F not turning on

IS there more i can remove to bypass or trick the main board

[dick_barton]

Re: Funai (Emerson) LF501EM4F not turning on

there is
0.75vdc/76vdc
0.74vdc/77vdc
1.2vdc/47vdc

Which set of leds is the 1.2V/47V reading from Led1, Led2 or Led3?

[jayjoesph]

Re: Funai (Emerson) LF501EM4F not turning on

Led1

[dick_barton]

Re: Funai (Emerson) LF501EM4F not turning on

They have been the problem set since the beginning.
Again just to confirm without having to read through the whole lot of posts again, had you confirmed that Led1 leds were definitely working by swapping them over say to Led2 or Led3?

[jayjoesph]

Re: Funai (Emerson) LF501EM4F not turning on

so from the attachment does the 3.3v need to reach the main board chip telling it the led circuit is okay ?

[jayjoesph]

Re: Funai (Emerson) LF501EM4F not turning on

They have been the problem set since the beginning.
Again just to confirm without having to read through the whole lot of posts again, had you confirmed that Led1 leds were definitely working by swapping them over say to Led2 or Led3?

yes