Many problems that circuit boards have may be repaired by replacing defective parts. You do not have to be an electronics engineer to remove and replace bad parts. Parts that commonly need to be replaced include capacitors, transistors and various electronic chips. If, through visual inspection or through circuit analysis, you can identify which part is defective, you can usually repair a circuit board.
Press the tip of your soldering iron against the solder point that is supporting the part you want to remove. Be careful not to touch the soldering iron to any other parts. The existing solder should soften and turn to liquid. If the solder does not melt, your soldering iron has not reached operational temperature or is not rated at a high enough wattage to melt that specific type of solder. Continue to hold the soldering iron tip in the melted solder.
Replace the part that has been disconnected from the circuit board. The old part should come out of the board easily. If it does not, make sure that all of the solder has been removed. Solder the new part into position, ensuring that each terminal is making contact with the correct port in the circuit.