How to Remove Corrosion From a Circuit Board

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All too often, a computer will computer stop working because of a bad connection. Over time, the copper on its circuit boards can corrode. The corrosion keeps signals from getting through. All it takes is one marginal connection to make the computer act strangely or put it out of commission. Use a screwdriver to try a simple trick--and possibly save yourself hundreds of dollars.


Step 1

Turn the computer off and unplug the power cord.

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Step 2

Open the computer with the screwdriver. Inside the computer, look for the expansion slots. These are long, plastic connectors, all in a row, on the largest circuit board in the computer (motherboard). A few of the slots may have circuit boards plugged in for video, multimedia or other applications. Remove all the circuit boards plugged into the expansion slots. If the boards have retaining screws, remove them first and set them aside. Note where the boards were originally located so you can put them back later. Remove the boards with a gentle rocking motion.


Step 3

Pick a circuit board you've just removed. Note the part that plugged into the expansion connector. It will have a series of neat copper traces ending at the circuit board's edge.

Step 4

Rub the pencil eraser firmly on these traces. The eraser will remove corrosion from the copper. You'll see the traces on both sides of the board, so be sure to clean both sides. Wipe the traces with a cloth to catch eraser rubbings and other debris.


Step 5

Repeat Step 3 for all the circuit boards you removed.

Step 6

Reinstall the circuit boards using your notes as a guide. Make sure the boards are seated firmly and completely. As long as the board goes back into the right type of slot, placement is not critical, but keeping the boards in the same slots ensures that you're restoring the computer to its original condition.

Step 7

Plug the computer back in and turn it on.

Things You'll Need

  • Pencil and paper

  • Pencil eraser

  • Screwdriver

  • Clean, lint-free cloth


This trick works for all vintages of computers that use the circuit board’s edge as a connector. It also works for other electronic appliances, but do not open any equipment that may have hazardous voltages inside.