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Insignia Flat Screen HDMI's Don't Work

philadelphia1

Jun 25, 2016
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Thanks for taking time to view my post :)

So, being that I live in Philadelphia and I'm currently in "covid stay-at-home mode" I thought i would bust out an old LCD television that a family friend recently gave me and try to troubleshoot its aliment.

No matter what device I connect to the HDMI ports, none of them work. A "No Signal" posts on the screen. I've thus far tried every trick under the sun to get this TV to work via Googles' help.

I disconnected the power and held in the power button for 30 seconds and restarted. I reset the televisions settings by going into the basic settings menu. I looked to upgrade the firmware but its a stupid (as opposed to smart) television. I watched a few YouTube videos and cooked the main board in the oven at an feeble attempt at a re-flow of the HDMI's IC chip. I even used a heat gun at an re-flow attempt, all to no avail.

I scoured internet endless hours looking for a secret service menu on the tv or even a technicians service manual and came up totally empty handed.

All the CAPS on the main board look fine and none appear bubbled. I'm taking a wild guess and thinking perhaps the board and or IC was hit and damaged by lightning or a power surge?

The TV will work when the cable box is connected at the component level with 3 Rca's. But the picture looks awful in standard definition. I can't hook a high def box up to the Tv without an HDMI connection.

What are your guys best guesses as to what is going on here? Faulty HDMI main board IC? Perhaps its another board on the television causing the problem? I'll post some pics of the main board.

Insignia Model # NS-46L550A11
MFG June 2010
Main Board Part # 715G3620-M01-000-005K

I'd be more than happy to try what's suggested or take additional pictures.

-http://www.imagebam.com/image/f80b8b1340898755
-http://www.imagebam.com/image/6f60b91340898760
-http://www.imagebam.com/image/577e221340898768
-http://www.imagebam.com/image/96d9011340898778
-http://www.imagebam.com/image/cd9b111340898805
-http://www.imagebam.com/image/e1bfc01340898819
-http://www.imagebam.com/image/168f9e1340898827
 

Cirkit

Oct 28, 2015
155
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Oct 28, 2015
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155
Before you suspect the HDMI IC, download the datasheet and check for the appropriate supply voltages to its pins. It looks as though there may be some regulators near it. Did you manage to find a service manual for the TV?
 

philadelphia1

Jun 25, 2016
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I can't find anything remotely helpful with regards to this television. The only thing I've come across is the OEM manual, which in of itself is useless.
 

Cirkit

Oct 28, 2015
155
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I can't find anything remotely helpful with regards to this television. The only thing I've come across is the OEM manual, which in of itself is useless.
Look for the part number on the HDMI IC and then search for its datasheet.
 

philadelphia1

Jun 25, 2016
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I took a high resolution picture of the chip and can't make anything from the writing on the chip. It kind of looks faded, even if i blow it up several 100 percent.
 

Cirkit

Oct 28, 2015
155
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I took a high resolution picture of the chip and can't make anything from the writing on the chip. It kind of looks faded, even if i blow it up several 100 percent.

Try looking at it from an angle.
 

Cirkit

Oct 28, 2015
155
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The part number is: SiI9287BCNU

You can find a basic pin-out if you search online.

With the TV off, carefully trace with the continuity mode on a multimeter two points where you can safely measure the voltage on pins 9 (positive) and 28 (negative) of that IC.

Set the multimeter to voltage mode and measure the voltage at the two points you found above with the TV on.
 

philadelphia1

Jun 25, 2016
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Jun 25, 2016
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Yea, like i said, I can't find anything.... Anyone else have any suggestions on what might be going on with this tv?
 

philadelphia1

Jun 25, 2016
20
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The part number is: SiI9287BCNU

You can find a basic pin-out if you search online.

With the TV off, carefully trace with the continuity mode on a multimeter two points where you can safely measure the voltage on pins 9 (positive) and 28 (negative) of that IC.

Set the multimeter to voltage mode and measure the voltage at the two points you found above with the TV on.

Ok CirKit, Thanks!

Fortunately i was able to find the datasheet. Am i looking for a voltage at pins 9 and 28 or just confirmation of continuity?
 

philadelphia1

Jun 25, 2016
20
Joined
Jun 25, 2016
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The part number is: SiI9287BCNU

You can find a basic pin-out if you search online.

With the TV off, carefully trace with the continuity mode on a multimeter two points where you can safely measure the voltage on pins 9 (positive) and 28 (negative) of that IC.

Set the multimeter to voltage mode and measure the voltage at the two points you found above with the TV on.

Although it's very difficult to see and count the pins, it appears as though I'm getting continuity at pins 9 and 28. I used a magnifying glass to help count out the pins.
 

Cirkit

Oct 28, 2015
155
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Oct 28, 2015
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If you have continuity between pins 9 and 28 with the TV off, you will need to first trace the regulator that supplies the IC and any bypass capacitors for it. How long did you hold the probes on the pins to confirm continuity?
 

Tha fios agaibh

Aug 11, 2014
2,252
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Aug 11, 2014
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2,252
If you you still have no luck, you can buy a component to hdmi converter box rather inexpensively. (If it has component output)
 
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