Q&A for How to Test Resistors

Resistors are color-coded; one end should have a gold, silver, or white band. That band represents the resistor’s tolerance. Begin by translating the colored bands into numbers and recording those numbers. For the first and second colored bands, the values are as follows: Black = 0; Brown = 1; Red = 2; Orange = 3; Yellow = 4; Green = 5; Blue = 6; Violet = 7; Grey = 8; White = 9.

A resistor is in place to restrict current. A faulty resistor is most likely an over-current issue somewhere in the circuit. The constant heating and cooling can take its toll. A fuse can blow for multiple reasons, its primary function is circuit protection. Ideally, the fuse should blow so as to protect the other components (your resistor) in the circuit.

No, it isn't. What happened is that the resistance of your resistor was low enough to trigger a continuity reading on your multimeter. If you read your multimeter's manual or spec sheet, you will find that the maximum continuity resistance is higher than your resistor's resistance.

If the resistor is burnt beyond recognition, you can check it with the diagram that came from the box or from the internet. Check the PCB, as most PCBs have diagrams printed on them. It may be hidden behind the resistor or around the resistor if the print is not available or if it's burnt. You can try and guess what the value is by calculation or by obvious means (like checking the resistor next to it), though it may be hard because there may be more than one resistor in a circuit. If you do find the correct value, you must check the circuit; resistors rarely burn.

It denotes a tolerance range of +/-5. A silver denotes a tolerance range of +/-10%.