White lines at top of TV

I had the same problem with horizontal white lines about 4 inches at the top of my 5 year old 27AF43 Toshiba. Solution, I found by google was to replace C407 but no directions. Here is how I did it.

First is to locate a new polarized 100uf 35V capacitor. I was able to buy 5 of these at a local electronic parts store for $2.50.

Next is to open up the TV. Turn off the TV and unplug all wires, place TV screen side down, remove the seven large screws, three on each side and seventh a couple of inches up from the bottom and about nine inches in from side. Then remove the two small screws in the area where the cables plug in. Gently lift off the back cover.

Put a large magazine or newspaper over the bottom part of the picture tube to protect if from scratches.

Next is to pull out the cicuit board at the bottom of the TV, it's the only one. Clip the cable ties holding some of the wires to give more freedom of movement and then gently pull up on the board. It doesn't need any fidling with clips or tabs or such, just pull straight up. You don't need to disconnect any wires.

Then locate capacitor C407. It is black and marked on the cicuit board and is 3 1/2 inches in from the edge and right by the corner of a heat sink. It will have 100uf 35V written on it. Note which side is the negative (this is important). It will be the same side as the other capacitors close to C407.

Next is to replace C407. Take some measurements from the edges of the cicuit board so you can locate C407 (from the bottom) and then flip the board over and locate C407's leads. Draw a circle around its leads with a felt pen. Us a fine tipped soldering iron and a solder ****** to remove the solder. Be careful with this. Might take a couple of goes but eventually you will beable to wiggle C407 and it will come out.

Put the new capacitor in and make sure the negative is on the correct side (this is important). Solder the two leads and be very careful the solder doesn't bridge between the two leads. Let it cool for a few minutes then use a pair of side cutters to cut off the excess leads.

Slide the circuit board back and push gently down until it snaps into position.

Remove the protective magazine or newspaper.

Use a couple of new cable ties to replace the ones you cut.

Replace the back cover being careful that the power cord is positoned correctly into its little notch. Replace the two small screws and the seven large ones.

Reattach the cables. Cross your fingers and turn on the TV. With luck your white lines will be gone.

Good luck

Brian
VE6IMB

Same problem on a Toshiba 27DF46 fixed by replacing capacitor C407 (100uF 35V.) The faulty capacitor looked absolutely normal, no bulges or leakage.