32" Dynex DXL3210A Won't Power On

[tieny]

I have a 32" Dynex, model number dxl3210a, that seems to be stuck on standby. The red standby light is on however nothing happens when I press the power button to turn on the TV. Opened the back don't see any blown caps and checked the fuses already. Would the power supply board be of suspect?

[Silviyius]

Re: 32" Dynex DXL3210A Won't Power On

if you get a standby light I would suspect the main board has a issue. Btw what is that gunk below rf6 cf5?

[tom66]

Re: 32" Dynex DXL3210A Won't Power On

Are the connectors on the power supply labelled?

Loving the imitation Elna vents on the crappy JH caps...!

[retiredcaps]

Re: 32" Dynex DXL3210A Won't Power On

I count 6 voltage regulators on the main board. Check them all to make sure they are in spec.

[tieny]

Re: 32" Dynex DXL3210A Won't Power On

Hmm, that gunk seems to be a blob of solder.

Yes the connectors are labeled, photo is below.

I measured a few voltage regulators, I feel some of these seem odd but I'm not sure.

N604
8JH 1117H
pin1-0.58v
pin2-1.84v
pin3-3.32v

N602
8JH 1117H
pin1-2.07v
pin2-3.32v
pin3-5.31v

N611 (Largest one)
AZI0845 ADJEI 829J43
pin1-3.84v
pin2-5.11v
pin3-8.36v

[tom66]

Re: 32" Dynex DXL3210A Won't Power On

What is the voltage on pin 5V1?

[tieny]

Re: 32" Dynex DXL3210A Won't Power On

There are two pins that are labeled 5V1. The higher pin reads 5.32V but the lower pin gives me a reading of 0V.

[tom66]

Re: 32" Dynex DXL3210A Won't Power On

There are two pins that are labeled 5V1. The higher pin reads 5.32V but the lower pin gives me a reading of 0V.

Okay that suggests good standby power but no run power. Do PON or lower 5V1 vary at all when you press the power button?

[tieny]

Re: 32" Dynex DXL3210A Won't Power On

Hmm, It seems when I measure either PON or that 5V1 and press the power button, the TV turns on perfectly. I guess the TV will turn on only when those pins are grounded? PON measures 3.05V and 5V! measures oscilating between 5.14V to 5.16V.

[tom66]

Re: 32" Dynex DXL3210A Won't Power On

Hmm, It seems when I measure either PON or that 5V1 and press the power button, the TV turns on perfectly. I guess the TV will turn on only when those pins are grounded? PON measures 3.05V and 5V! measures oscilating between 5.14V to 5.16V.

My guess would be a cold joint on the PON connector (or on the PSU somewhere); when you flex the board slightly (pressing in your meter probe) it turns on. So inspect the board for cold or dodgy solder joints.

[tieny]

Re: 32" Dynex DXL3210A Won't Power On

I did remember I saw a small spark when I touched to measure the GND pin between the PON and 5V1 pins. I just resoldered the pin and now the TV is able to turn on perfectly!

[tom66]

Re: 32" Dynex DXL3210A Won't Power On

I did remember I saw a small spark when I touched to measure the GND pin between the PON and 5V1 pins. I just resoldered the pin and now the TV is able to turn on perfectly!

Fantastic!

[tieny]

Re: 32" Dynex DXL3210A Won't Power On

Eh, bad news. I left the TV on for 20 minutes, and it just shut off and I can't get it to turn back on now. While on standby (red LED) PON reads 3.05V, higher 5V1 - 5.30V, lower 5V1 - 5.26V. Would this be a new problem?

[tom66]

Re: 32" Dynex DXL3210A Won't Power On

Eh, bad news. I left the TV on for 20 minutes, and it just shut off and I can't get it to turn back on now. While on standby (red LED) PON reads 3.05V, higher 5V1 - 5.30V, lower 5V1 - 5.26V. Would this be a new problem?

Probably another issue, if there's one cold joint it's possible there are several more... Check other outputs, check cables seated properly, check for cold joints.

[tieny]

Re: 32" Dynex DXL3210A Won't Power On

Should PON and 5V1 read 0V during standby like before? And then voltages would only appear once the power button is press?

So far I just reflowed all the output connectors on the PS board but no luck.

[tom66]

Re: 32" Dynex DXL3210A Won't Power On

Should PON and 5V1 read 0V during standby like before? And then voltages would only appear once the power button is press?

So far I just reflowed all the output connectors on the PS board but no luck.

I think they should. Does the screen glow when it's stuck in standby?

[tieny]

Re: 32" Dynex DXL3210A Won't Power On

nope, the screen is completely off.

[ben7]

Re: 32" Dynex DXL3210A Won't Power On

nope, the screen is completely off.

Might be an issue with the backlight inverters.

BTW, those JH caps DONT last long at all in smps, they should be changed out.

Kind of wacky having JH and CHANG caps in a PSU with some Rubycons too.. xD

[tieny]

Re: 32" Dynex DXL3210A Won't Power On

Oh those rubycons were just spares I just swapped since I had a few extra with the same specs.

How would I go about checking the inverters? Wouldnt the TV turn on (blue led) but just with no picture then?

[tieny]

Re: 32" Dynex DXL3210A Won't Power On

Photos of the inverter board, So far only checked the fuse, but it doesn't seem open. Also I'm about to buy an ESR/Capacitance meter, any suggestions or recommendations?