PL2010M flickers once when turned on, then black

[primuspaul]

Any way to fix? Anything else to check? I saw no obvious bad caps.

[primuspaul]

Note this unit has an external psu.

[primuspaul]

Tried a different compatible 12v5a psu and same result.

[CapLeaker]

I see some bad caps on the main board like C505. Also take out and reseat that square IC.
Probably your back light disappears, because of the inverter board or the lamps. Measure the resistance of the high voltage secondaries of the 6 transformers. If they are not within 2%, the inverter board won't work. Also check those blue high voltage caps and the connectors for bad solder joints. Generally look at anything that has weight and or high heat for cold solder joints.

[primuspaul]

I see some bad caps on the main board like C505. Also take out and reseat that square IC.
Probably your back light disappears, because of the inverter board or the lamps. Measure the resistance of the high voltage secondaries of the 6 transformers. If they are not within 2%, the inverter board won't work. Also check those blue high voltage caps and the connectors for bad solder joints. Generally look at anything that has weight and or high heat for cold solder joints.

How can I tell C505 is bad? I don't see the usual signs like swollen top or leaking.

[primuspaul]

I see some bad caps on the main board like C505. Also take out and reseat that square IC.
Probably your back light disappears, because of the inverter board or the lamps. Measure the resistance of the high voltage secondaries of the 6 transformers. If they are not within 2%, the inverter board won't work. Also check those blue high voltage caps and the connectors for bad solder joints. Generally look at anything that has weight and or high heat for cold solder joints.

Is there some way for me to test the capacitors without desoldering each one? The only equipment I have is CL800 clamp meter and a Fluke 115.

[primuspaul]

I found some brown residue on C61. Gonna try to replace that and see if it works.

[CapLeaker]

That c505 got hot as the sleeve shrunk. Worth checking it out. I’ve seen caps they look brand new, yet have no capacity. So you can’t go by looking at capacitors alone. The reason you backlights fail is because a very high chance of one or two transformers being bad.

[primuspaul]

That c505 got hot as the sleeve shrunk. Worth checking it out. I’ve seen caps they look brand new, yet have no capacity. So you can’t go by looking at capacitors alone. The reason you backlights fail is because a very high chance of one or two transformers being bad.

OK. I'll see if I have a compatible cap and replace c505 and c61.

[primuspaul]

That c505 got hot as the sleeve shrunk. Worth checking it out. I’ve seen caps they look brand new, yet have no capacity. So you can’t go by looking at capacitors alone. The reason you backlights fail is because a very high chance of one or two transformers being bad.

Replaced both. Same symptoms

[CapLeaker]

Check the resistance of the 6 transformers and write it down.

[primuspaul]

Check the resistance of the 6 transformers and write it down.

Which items are the transformers and how do I test them? Do I need to desolder them to do this?

[Sam Scarbo]

This chip looks bad. Is it burnt?

[CapLeaker]

Hard to tell. Sometimes a picture does 100% showing a hole or a chip missing. But under a microscope it looks different and nothing wrong. Happened to me just a couple of days ago to one of my threads. Clean the chip up and look again, I that chip would be dead, your monitor wouldn”t be doing what it is doing now. Again, check the resistance of these transformers,

[CapLeaker]

Which items are the transformers and how do I test them? Do I need to desolder them to do this?

On the board with the backlights (second pic, in your first post) measure the resistance of these 6 red looking transformers on the secondary high voltage side and note it down. Then compare them to each other. No you don’t have to take these transformers out.

[primuspaul]

Hard to tell. Sometimes a picture does 100% showing a hole or a chip missing. But under a microscope it looks different and nothing wrong. Happened to me just a couple of days ago to one of my threads. Clean the chip up and look again, I that chip would be dead, your monitor wouldn”t be doing what it is doing now. Again, check the resistance of these transformers,

Is that better?

[primuspaul]

On the board with the backlights (second pic, in your first post) measure the resistance of these 6 red looking transformers on the secondary high voltage side and note it down. Then compare them to each other. No you don’t have to take these transformers out.

Not sure I measured the right pins. https://app.cimediacloud.com/r/XYrWmscRCtQC

[CapLeaker]

Not sure I measured the right pins. https://app.cimediacloud.com/r/XYrWmscRCtQC

The measuring points are correct, you just had your meter set to capacitance, not the Ohm setting (resistance). So you have to measure again and write the results down.

[CapLeaker]

Is that better?

could be some other residue on the chip. That what it looks to me.

[lotas]

U601 - TPA6030A4