Measure the resistor with a multimeter before you solder it in. Colours are easy to misread, especially brown, red and orange.
What the message means
Bands are read from the end opposite the tolerance band. Light, worn or similar colours cause mix-ups, and a wrong value can burn an LED or leave a transistor off.
Fix it in this order
- Remove the resistor from the circuit, or measure before fitting it.
- Set the meter to the resistance range and read the value.
- Compare it with the colour chart. The meter wins if they disagree.
- Find the tolerance band, usually gold or silver, and read from the other end.
- Keep resistors in labelled bags.
- Remember a resistor in a powered circuit gives a false reading.
If you see this, do this
| You see | Do this |
|---|---|
| Value is 10 times off | A band misread, such as brown and orange. |
| LED too bright or too dim | Check the series resistor value. |
Related
LED current limit, multimeter use.
Last reviewed: November 2026. These are the usual causes and the order that finds them fastest. Test on your own board; clones and cables differ.