Insignia NS-48D510NA15 Won't Power Up

[0S1R1S]

Hello all, taking a break from the Vizio I've been working on to try and save this Insignia I picked up from the scrapper.
Panel is good from a visual inspection, no apparent cracks.
Plugging in the TV gives me a solid red light on the indicator panel.
Pressing power, nothing changes.
I opened the unit up and found a very simple design. Power board, main board, T-Con, speakers, and a button board.
Power supply has ~17V on the two 16V pins, 3.4V for the STB pin, 12.8V for the 12V pins, all as they should be. But the set won't power on.
So, a main board issue? Anyone care to advise me further on what to look for first, on what board?
Pictures attached.
Thanks in advance.

[dick_barton]

Re: Insignia NS-48D510NA15 Won't Power Up

Does the backlight come on when you power on with the mainboard disconnected.

[CapLeaker]

Re: Insignia NS-48D510NA15 Won't Power Up

Post the pin out names with the voltages measured. So we can see what's going on.

[0S1R1S]

Re: Insignia NS-48D510NA15 Won't Power Up

Does the backlight come on when you power on with the mainboard disconnected.

How would I power it on with the main board disconnected? The button board is attached to the main board.

[budm]

Re: Insignia NS-48D510NA15 Won't Power Up

Look at the bottom side of the power supply board, the pins for the connector that goes to the main board are labeled, so the the reading of each pin then report the readings with pin names for each pin so we will know what are missing.

Some of the power supply boards may have built-in pull-up resistors to allow self test of the power supply board without having the main board connected, when AC power is applied the power supply board then the switched power supply sections will come on, and the backlights will also come on.

http://www.shopjimmy.com/hisense-170...pply-unit.htm#
Hisense/Insignia 170452 Power Supply
Pictures provided by shopjimmy.

[0S1R1S]

Re: Insignia NS-48D510NA15 Won't Power Up

Sorry for the lack of updates or replies. I ordered a main board for $30, threw it in, and works just fine.

[vinceroger69]

Re: Insignia NS-48D510NA15 Won't Power Up

Thanks for the update glad a replacement mainboard fixed the tv.

[frannyeno10]

Re: Insignia NS-48D510NA15 Won't Power Up

This same thing happened to me recently.
But I bought a new power supply board on ebay and it's still not working.

When I plug the tv with the new board a red light comes on, but it won't turn on. Then, when i unplug the TV i can head the TV's speakers make a sound (as if shutting down) meaning there the new board is probably ok.

What could be the problem? What's the next part i should replace?

Also, i have a multimeter, is there anyplace i can test with it?

[budm]

Re: Insignia NS-48D510NA15 Won't Power Up

This same thing happened to me recently.
But I bought a new power supply board on ebay and it's still not working.

When I plug the tv with the new board a red light comes on, but it won't turn on. Then, when i unplug the TV i can head the TV's speakers make a sound (as if shutting down) meaning there the new board is probably ok.

What could be the problem? What's the next part i should replace?

Also, i have a multimeter, is there anyplace i can test with it?

First thing you need to do is to make the Voltage measurement on the power supply connector that goes to the main board when TV is off and when power switch is activated so we can see what it has and does not have. Read post #5.

[brucetv]

Re: Insignia NS-48D510NA15 Won't Power Up

We've seen a lot of backlight problems with this model. Turn the tv on and flash a bright flashlight into the panel and use the remote to hit menu and see if you can see the letters of the menu with the flashlight. If you can you have blown backlight led's. We have gotten by changing the eeprom chip to fix that problem on about 30% of them. If your soldering skills are not that good and the voltages on the power supply look good it's usually the main board.