I repaired two different/distinct 245BW - in both cases one of the three 68 ohm 5% two watt (2W) 5% resistors was an open circuit. These resistors are in series. On the first repair the equivalent series resistance ( ESR ) capacitor meter was reading high, and suspect on two capacitors. So I replaced them, they were two smaller caps on the power board in uF and size. One of the end/outer 68 ohm resistors was an open circuit, the location on my power boards/boards were on the circuit board edge. I measured the capacitance of the two suspect capacitors, that were removed; and they were within tolerance. (22 uf 50 V, 15.7 mm high, radial, dia 5 mm and 22 uF radial, 50 Volt , dia 5 mm, 16 mm high. Both were aluminum electrolytic ( I suspect I replaced them with 65+ or greater Volt rated caps see/search for term derating electronics) ESR reading on both caps were just "Bad" - suspect other circuitry prevented an accurate reading with the ESR meter. I replaced all three of the 68 ohm resistors 2W (color code blue (6) grey (8), black (0), gold (5%).
Note I had no problem measuring the three qty 68 ohm resistors while they were still installed in the board (i.e., you do NOT have to remove these resistors to measure the ohm value (in this case to get a correct reading) - at least on the two boards I repaired - your power board might be different - doubtful; but possible) Harbor freight used to have coupons for free multi-meters BTW which measures ohms - you tube has a video on taking about the monitor.
On the second monitor that failed, I went straight to the group of three resistors (68 ohm) that are "glued together", one had become open circuited. Note, I opened the case up, when the screen/monitor/LCD started to act "funny" I did not wait for a totally black screen/LCD. I tested the caps for ESR all were within spec, one was had a higher ESR than I like so but was within specification per the ESR meter. I went ahead and replaced it (not worth opening the case again since I already had it in stock). Both 245BW monitors are back working. I did tear apart the resistors, I was curious if they were wire wound and if so, were/are they non-inductive wire wound - the one on my two monitors are metal film resistors, the one resistor I torn apart anyway. Basically I suspect the connector from the resistor leads on these 68 ohm resistors separates from the ceramic body/film coating due to thermal cycling. I replaced the just in case (1 uF, 50 V, radial - aluminum electrolytic 8 mm dia, 19 ,mm high, ESR 3.26 ohms (on the first repair above this cap measured 0.226 ohms for ESR) was tempted to use a film capacitor, and I might of, I can't remember distinctly. Again, I probable use a 63 Volt (or greater) rated capacitor as a replacement.
Anyway, of note, I replaced the 2W 68 ohm resistors, with 68 ohm 5%, 5 Watt resistors - note the leads of the resistors have to be extended, and wire that extends the lead has to fit into the circuit board hole. (one can cut off the leads of another 5 Watt resistor to do this (the wire needs to be stiff I'd STRONGLY advise against using stranded wire (mechanical stability)- these 5W resistors seem to be commonly available) and are obviously at least twice the size, in length and width (they do not lay on the board, but are mounted vertically) and and so they have to be bend over so as not to touch the metal frame (top), note these resistors are on the edge of the board(s) I repaired. Note, your version of the power board might be different, so this might not work for you, not probably; but again possible. I used heat shrink tubing on the resistor lead that exits resistor form the top, I did not the lead or case for that matter touching anything else, if I did it again, I would use heat shrink tubing that covered the top 25%or so of the resistor body, including the one "high side" resistor lead. Be absolutely positive if you use 5W resistors as replacements the bare resistor leads do not touch any other components/ or the metal enclosure .
Search for "De-rating electronic" components is a good way to prolong the life of electronic components. I find it useful on the electronic stuff I repair.
If another one 245BW starts to fail, and a capacitor(s) is or are not bulging or showing other visual signs of failure - I am going straight for the resistors. I doubt I will take the time even to measure the cap's ESR. Note, this is due to just two 245BW failing - not extensive experience by any metric.
Supposedly aluminum electrolytic capacitors should last 18 years I read somewhere. (after infant mortality -electronic) perhaps on that article about the early 2000's (2004) capacitor plague (Wiki). I don't think the 245BW was first manufactured until the middle of 2007. .
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