Repairing LG 17LX1R LCD Television Power board

Here is a decent looking LCD TV/monitor that would no longer turn on. I expected a few capacitors etc. that needed to be replaced. In this case, it was a single diode at the cost of 29cents and a bit of over 1 hour of labor. It also shows the importance of a good visual inspection. A new power board for this TV would have cost somewhere around 100$

Step 1 — Power board 

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  Here is the LG 17LX1R that will no longer turn on.
  
  
  
  
  
  


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  Remove the cover from the stand by
  
  
  
  
  
  
  
  
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    simply pressing down on the two tabs. The cover will come off easily
    
    
    
    
    
    
  
  
  
  


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  Remove the four screws that hold the stand assembly to the chassis.
  
  

Step 2 

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  Here again are the four screws to be removed from the stand.
  
  
  
  
  
  


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  Remove the eight Phillips screws that hold the back to the chassis. Once the screws are removed, the back will simply snap off. No excessive force or tools are needed.
  
  
  
  
  
  


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  This is the view with the back off. Time to remove the metal shield. It is fastened with six Phillips screws.
  
  

Step 3 

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  Remove the two on the left
  
  
  
  
  
  


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  Remove the two on the right.
  
  
  
  
  
  


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  Remove the two on top.
  
  
  
  
  
  
  
  
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    Once the six screws are removed the shield can be lifted away easy.
    
    
  
  
  
  

Step 4 

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  After the shield is removed, the power board as well as the main board are immediately visible.
  
  
  
  
  
  
  
  
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    Power Board
    
    
    
    
    
    
  
  
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    Main Board
    
    
    
    
    
    
  
  
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    Fuse
    
    
    
    
    
    
  
  
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    Check all capacitors for blown tops and/or leakage.
    
    
    
    
    
    
  
  
  
  


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  Here is the importance of a good visual inspection. Brown discoloration around Diode D102 is good evidence of a short circuit, possible blown component.
  
  
  
  
  
  


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  Disconnect all connectors from the power board
  
  
  
  
  
  
  
  
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    Remove the four screws that mount the power board to the chassis.
    
    
  
  
  
  

Step 5 

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  Chassis with the power board removed
  
  
  
  
  
  


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  Discoloration of the back side of the power board points again to a bad diode.
  
  
  
  
  
  


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  Unsolder the diode from the power board
  
  
  
  
  
  
  
  
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    Replacement diode
    
    
    
    
    
    
  
  
  
  

Step 6 

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  Here is the unsoldered diode. description on the diode reads LT526 IN4007. Arranged to purchase at $0.29 per diode.
  
  
  
  
  
  


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  Solder the new diode onto the power board. Use a pair of tweezers or hemostat to hold the diode in place while soldering.
  
  
  
  
  
  


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  Diode replaced, clean the board with isopropyl alcohol to get rid of any debris or old flux.