Sunday, February 26, 2012

Home TV Repair, Part II

Braced with knowledge gained from YouTube, I was now going to attempt my own TV repair.

The first trick was to remove the support stand. I unplugged everything from the TV, set it upside-down on the den rug, held it between my knees, removed three screws from the base of the support stand, and it lifted right off.  Okay, so far so good.

I gently laid the TV face down and examined the back, ignoring the "No serviceable components inside.  To be open by trained personnel only" message.  Most obvious were the four mounting screws in back.  Those came out.  Next were the screws along the edge of the back.  I could see something like 17 screws around the border.  Many were in deep "wells."  Without a magnetized screwdriver, there's no way I could completely remove the screws, but I could at least unscrew them, and they should not present a problem when I lifted the back off.

Tip:  I grabbed a couple of zip-lock sandwich bags from the kitchen to keep the screws organized.  Last thing I needed was for one of the cats to come along and start batting loose screws off the coffee table.

17 screws unscrewed later, I tried lifting the back off the TV, and it wouldn't come up.  Then I noticed an 18th screw near the component plugs.  I removed that, and it still wouldn't lift off.  Wow, a 19th screw was hiding between two plugs in back.  Easy to miss.  And the back still wouldn't lift off.  Then I noticed the VGA plug with its two hex-shaped screws.  I removed them, and AT LAST, the back easily lifted off.

Lesson learned:  If the back of your TV is resisting removal, don't try to force it -- look for more screws, in particular in and around the various plugs in back.

Now I was looking at a metal cage covering the motherboards.  More screws to remove the cage, and a couple of things to unplug to get the cage loose.  That done, I was now looking at two motherboards.  One was the power supply board, and the other the CPU board.  The power supply board was identifiable by looking a bit more "primitive" with resistors, some possible transistors (are they still made?) and, in particular, capacitors sticking up.

Sure enough, I could see two small capacitors were bulging on top.  The rest look flat.  There were several ribbon cords with different connectors attached to the power supply board.  Just to be sure, I photographed the board, then unplugged everything, and removed still more screws holding the board in place.  The board lifted up easily.

Tip:  If you have curious pets, cover the TV with the back to keep pets out.  I also repositioned the cage, and put the zip-locked screw bags in prior to covering to keep our cats out.  (Or, I could have just shut the door to the den.  Yeah, that would have worked too.)

With a closer look at the power supply board in better light, I still could not make out the writing on the capacitors while still they were still mounted.  I would have to remove then to read them, but I did recall in one of the better YouTube videos, the guy mentioning the capacitors he replaced as being 1000 microfarads (µf).

I headed off to Radio Shack an electronics store to buy a soldering iron and supplies.  I wound up selecting a solder kit with a 30-watt soldering iron, plus some basic tools like small needle-nose pliers, diagonal cutters, solder, etc.  In addition I purchased a de-soldering bulb (basically a little rubber bulb you use to suck up old, melted solder) and a tin of flux, which in hindsight I probably didn't need.  On speculation I also grabbed two 1000 microfarad capacitors just in case that's what I needed.

Total purchase:  $32, and that was largely for the solder kit and supplies.  The capacitors themselves were $1.70 each.

Next up:  The replacement

No comments:

Post a Comment