I always start there because if any damage does occur trying to get between the cracks in the plastic halves then hopefulyy it won't be noticeable when it is put back together. When you are happy that there are no possible screws holding the casing together you should start to pry open the front / rear halves of the casing starting at the bottom of the monitor. Sometimes there are screws hidden behind rubber seals. Most of these units have an extra 4 screws fitted where the wall panel would be fitted holding the plastic casing to the metal inner casing. Capacitors normally have the negative side marked with a long bar on the sleeving and most boards have the negative side marked up too BUT I have seen recently many occasions ( mainly from one manufacturer) to mark the positive on the printed circuit board making it confusing unless you noted from the start what side goes where. These capacitors are polarised so you MUST remember which way round the old one was fitted.

Means that the capacitor has a low internal impedance which is good when dealing with ripple currents on the supply lines. Low ESR is also a good idea if someone has something available. High temperature means that they are rated at 105 degrees and not the old standard 85 degrees. Always use high temperature good quality capacitors and if the store you purchase from doesn't have the value / voltage you are looking for then get the next highest value. carefully note the values and quantities you need, most likely won't be all the same value or the same voltage. You'll have to find the power supply board, which is the first place to start looking, and carefully note what capacitors look stressed or domed, maybe even leaking. They are normally the source of loss of backlight and make it look like the set has turned off. I'd start by removing the power leads, opening it up and doing a visual check of the boards looking for domed electrolytic capacitors.

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