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The component appears to be damaged, but the datasheet for the board in question shows that this is a 47k ohm variable resistor. Looks like a trimmer, but not 100% sure.

However, I've been trying to find a similar looking component with the same rating to no avail. Most SMD trimmers that I have found with a similar rating have two terminals in one side, and one terminal on the other. The board in question is a controller board attached to a LCD panel.

Datasheet: https://datasheetspdf.com/pdf-file/762847/AUO/M200RW01-V0/1

enter image description here

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Nick U
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2 Answers2

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They're similar to obsolete Panasonic EVM1U 4mm trimpots, though without accurate dimensions it's hard to tell.

enter image description here

It does not look damaged, it might be corroded or it could just be cosmetic corrosion of the Ag plating.

It's obviously connected as a rheostat. Note the current position of the wiper and turn it back and forth from end to end a few times, then return the wiper to the previous position (with power off) and see if that makes any difference.

You could also probably replace it with a 22K resistor if it's really bad, but if cranking it end-to-end a couple times makes no difference your problem is probably somewhere else.

Be careful to get a tool that fits the trimpot properly and proceed gingerly, it's easy to damage those small parts with ham-fisted twisting and thrusting.

Spehro Pefhany
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  • That looks VERY similar, but unfortunately it isn't the same model. Knowing that it is an obsolete component does give a hint towards a solution, so I'll mark this as the solution. Edit: I zoomed in further with a camera and noticed a crack within. Took the component off the board, gave it a few twists and didn't get any measurements beyond the 6-9K range. – Nick U Sep 25 '19 at 17:24
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It is very likely a trimmer. Look at that oddly shaped spring element with a dent. That's typical for trimmers.

For correct funtionality a trimmer needs only three terminals, with few exceptions. I guess the fourth terminal in this picture is to gain mechanical stability.

Two recommendations:

  • The device looks like it has suffered corrosion. This may be caused by water or aqueous solutions, but the rest of the board doesn't look like that. It also may be caused by overheating. So you should have a look on the attached circuitry for additional failures, because in normal operation overheating of trimmers should be prevented by design.

  • Desolder it and re-engineer the circuit to understand which terminals are needed to operate correctly. After desoldering it, you can easily see, which terminals are connected to the taper etc. You can select another trimmer perhaps with only three terminals which fits this landing pattern.

Ariser
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  • Will keep this information in mind, thanks. Overheating was the first assumption, as the component appears to be connected to a 12V rail. – Nick U Sep 25 '19 at 17:33