DYNEX 40" Model DX-L40-10A/4832 Will not power on.

[tomandrews86]

Re: DYNEX 40" Model DX-L40-10A/4832 Will not power on.

Time to find a main board then?

[tomandrews86]

Re: DYNEX 40" Model DX-L40-10A/4832 Will not power on.

As soon as I typed in my part number up popped several kits containing an eeprom and a few other components. How could I diagnose my problem back to this part? The ads say failure of the eeprom may cause the fault I am seeing, however the fix is obviously not guaranteed nor do they give any suggestion as to how to tell if yours is defective in the first place. The kits are going for $18-$20USD which is a deal compared to a whole new board IF its fixes my problem. The part in question is N14 and can be found in the service manual, I just do not know how to tell if its defective.

[CapLeaker]

Re: DYNEX 40" Model DX-L40-10A/4832 Will not power on.

it's kind of a gamble... how much does a new / used main board cost, or can you even get one?

[tomandrews86]

Re: DYNEX 40" Model DX-L40-10A/4832 Will not power on.

$85 for main board from shop jimmy, $15 for eeprom

[shawnjess72]

Re: DYNEX 40" Model DX-L40-10A/4832 Will not power on.

hi on the power board what would make all the voltage to be double then they should be like the 12v is 24 and the 5v is 10.6

[jthorsen3315]

Re: DYNEX 40" Model DX-L40-10A/4832 Will not power on.

I had a similar issue with this model TV. The red LED would be lit but I could not get it to turn on. If I unplugged the cord and plugged it back in I would hear a click and the TV could be turned on. After a month, though, even that trick wouldn't work and the TV would not come on at all.

I was able to fix it by desoldering all the Peace capacitors on the power board and replacing them with Nichicon ones. This seemed daunting to me at first since I have very little soldering experience but it only took me about two hours. There are a total of 18 radial caps (17 electrolytic peace caps and the one big blue one). Out of curiosity I tested the ones that I took off and the one that was bad was C814. My multi-meter was only measuring about 22 nF, way too low.

It seems the issue with this TV is the cheap Peace capacitors. I've had this TV for 6 years now and it only cost me about $30 in parts to fix it. That's way better than $300 to buy a new one.

[jcuria]

Re: DYNEX 40" Model DX-L40-10A/4832 Will not power on.

This is the exact symptoms I get...so I will test test the the three caps you mentioned.

[jcuria]

Re: DYNEX 40" Model DX-L40-10A/4832 Will not power on.

My set has the exact symptoms and troubleshooting results as the one reported by tomandrews86. Not sure I want to gamble $85 bucks on a main board. This model TV has a history of so many problems.....

[ZnsaneRyder]

Re: DYNEX 40" Model DX-L40-10A/4832 Will not power on.

I am getting no power on with this TV as well. I get the blue light that comes on, I get voltages, and I can't turn it back off.

[CapLeaker]

Re: DYNEX 40" Model DX-L40-10A/4832 Will not power on.

sounds like eeprom. freeze it with a can of air upside down and check if the tv turns on.

[ZnsaneRyder]

Re: DYNEX 40" Model DX-L40-10A/4832 Will not power on.

sounds like eeprom. freeze it with a can of air upside down and check if the tv turns on.

I was suspicious of the eeprom at first..........I will keep you posted, but I just got the TV to come on, after taking measurement of the 0V showing on the PW-ON wire, I wiggled the boards, and it jumped to 4V and it powered on!

I just resoldered and fluxed (kingbo) all the pins on the power and main boards (couldn't see broken solder joints) I also reflowed and fluxed the little SMT transistor and resistor that connects to the PW-ON on the mainboard.

I will let you know if it still comes back on...............

[ZnsaneRyder]

Re: DYNEX 40" Model DX-L40-10A/4832 Will not power on.

ITS GOOD!!!

The TV is fixed. Reflowing those solder joints was the fix, and I also resoldered ALL the connector pins. I reflowed with heatgun and generous Kingbo flux on it, the transistor that controls the PW-ON, but while I was in there, I upgraded the caps for the 16V 5V standby and 24V output, and the TV comes on a bit quicker, so that was also needed. All the old caps are still good, but they were ~10% below value, I changed them anyway.

[philtvman]

Re: DYNEX 40" Model DX-L40-10A/4832 Will not power on.

Just wanted to chime in for anybody who finds this thread through searching. My TV showed red standby, but was unresponsive to button pushes. The fix turned out to be replacing C811 (10uF/25V), C812 (10uF/25V), and C814(100uF/35V).

[frakncylons]

Re: DYNEX 40" Model DX-L40-10A/4832 Will not power on.

I was having the same problem as most here described. TV wouldnt power on but cycling power then turning on would usually work. It finally died last night. I replaced all the radial caps and reflowed some questionable joints today and now it works like a champ.

My backup plan was to buy the whole board from shop jimmy for $50.

Thanks all.

[neilc6]

Re: DYNEX 40" Model DX-L40-10A/4832 Will not power on.

Thanks to Unspun01 for initial solution. Replaced C811, C812 and C814. C814 was a little low around 86uF but one of the 10uF caps measured around 70 ohm esr and the other was a little high as well. Replacement caps measured around 2 ohms esr.

Difficult diagnosis since there is no visible bulging and the smaller electrolytics are less likely to fail than the larger values.

[Unspun01]

Re: DYNEX 40" Model DX-L40-10A/4832 Will not power on.

Hi neilc6:

I'm glad to hear my solution worked for you and any others who tried it

Take care.

[neilc6]

Re: DYNEX 40" Model DX-L40-10A/4832 Will not power on.

Thanks to Unspun01 for initial solution. Replaced C811, C812 and C814. C814 was a little low around 86uF but one of the 10uF caps measured around 70 ohm esr and the other was a little high as well. Replacement caps measured around 2 ohms esr.

Difficult diagnosis since there is no visible bulging and the smaller electrolytics are less likely to fail than the larger values.

Reported success a little too soon. Still having issues turning on. Relay clicks and standby light is on. Doesn't respond to on/off side button. Checked the rest of the electrolytics and they tested fine. Tried freezing the eeprom after removing the shield as well.

[Unspun01]

Re: DYNEX 40" Model DX-L40-10A/4832 Will not power on.

Hi neilc6:

You may also have to replace c842 on power supply (it may not look bad):

2000v 22 nJ
0.022uf 2KV 5%. High pulse DV/DT.

https://www.digikey.com/product-deta...235-ND/1532455