L42VC04U Blinking Blue LED

[speedypro]

I've replaced the main board with one bought off ebay. I see same issue. This made me believe it's a psu issue? I know these 17PW26-4 board has many issues but I see no physical faults; no swollen caps, or any faulty fets.

[ReeceyBurger123]

Re: L42VC04U Blinking Blue LED

Voltages tested at all ? Remove Mb connector and connect Psu if its working it will bring up all voltage rails 24v, 12v, 5v, 3.3v. Cant help further until you help us, what you expect us to list every fault with this set with no voltages lol

[speedypro]

Re: L42VC04U Blinking Blue LED

Remove Mb connector and connect Psu if its working it will bring up all voltage rails 24v, 12v, 5v, 3.3v.

Thanks. How to know what pin has x voltage at PL816? Schematics?

Based on the schematics at PL816, Im not getting those voltages. Bad transformer? The main huge cap is making a humming sound -- seems normal.

[ReeceyBurger123]

Re: L42VC04U Blinking Blue LED

Just look for the ones I listed, test each pin bud. Same on all 42" Pw26 boards btw.

[speedypro]

Re: L42VC04U Blinking Blue LED

Just look for thes one I listed, test each pin bud. Same on all 42" Pw26 boards btw.

See my edit.

[vinceroger69]

Re: L42VC04U Blinking Blue LED

Heres a schematic but im sure reece has mentioned in the past you just measure at the diodes? not sure if this scematic will match your board as they do alter them etc

[ReeceyBurger123]

Re: L42VC04U Blinking Blue LED

Not for the 17pw26 vince they are the same matey, but for example you cant use the 32" model pw26 (smaller tarfo and switchers) in a. 40" as it wont be able to supply the current. But the voltages are the same. 17pw25 is the one that changes it all the time.

[speedypro]

Re: L42VC04U Blinking Blue LED

Heres a schematic but im sure reece has mentioned in the past you just measure at the diodes? not sure if this scematic will match your board as they do alter them etc

Thanks but I've found the schematic. Just not getting those voltage.

[vinceroger69]

Re: L42VC04U Blinking Blue LED

so your not getting any voltages at all on that connector? not even the stanby ones

[vinceroger69]

Re: L42VC04U Blinking Blue LED

Not for the 17pw26 vince they are the same matey, but for example you cant use the 32" model pw26 (smaller tarfo and switchers) in a. 40" as it wont be able to supply the current. But the voltages are the same. 17pw25 is the one that changes it all the time.

Thank reece i will rember that info.

[speedypro]

Re: L42VC04U Blinking Blue LED

so your not getting any voltages at all on that connector? not even the stanby ones

Sorry, only the 3.3v, 24v and 5v.

[dick_barton]

Re: L42VC04U Blinking Blue LED

Thanks but I've found the schematic. Just not getting those voltage.

So what voltage do you have across the main capacitor C819?

[speedypro]

Re: L42VC04U Blinking Blue LED

so what voltage do you have across the main capacitor c819?

385vdc

[vinceroger69]

Re: L42VC04U Blinking Blue LED

Sorry, only the 3.3v, 24v and 5v.

so only the 12v missing

[speedypro]

Re: L42VC04U Blinking Blue LED

Let me do a proper test at pl816 and update with a little image.

[dick_barton]

Re: L42VC04U Blinking Blue LED

385vdc

With 385V your PFC circuit is working as it should.

[speedypro]

Re: L42VC04U Blinking Blue LED

With 385V your PFC circuit is working as it should.

But I tried a main board, not psu, off ebay and same?

Pin / Voltage:

1: 0
2: 0
3: 0
4: 7.8v
5: 0
6: 0
7: 0
8: 0
9: 0
10: 0
11: 11.87v
12: 11.87
13: 0
14: 4.99
15: 3.4
16: 3.4
17: 5.13
18: 3.4
19: 5.13
20: 3.4
21: 5.13
22: 3.4
23: 0
24: 0
25: 0
26: 24v
27: 0
28: 0

Would the inverter board plays a role with the flashing blue led?

[vinceroger69]

Re: L42VC04U Blinking Blue LED

Im still learning so bear with me but what do pins 1/3/5/7/9 do? as 12v is missing too them

[speedypro]

Re: L42VC04U Blinking Blue LED

Im still learning so bear with me but what do pins 1/3/5/7/9 do? as 12v is missing too them

Im going off the schematics:

[vinceroger69]

Re: L42VC04U Blinking Blue LED

just found a better schematic it dosnt look like those pins are used i wonder if you have another bad mainboard?