⚠️ Safety First: Before beginning, disconnect the machine from its power source to avoid any risk of electric shock.
- Set your multimeter to measure resistance (Ω / ohms).
- Disconnect the potentiometer wiring from the circuit board.
- You can test at the end of the wiring harness or directly on the potentiometer.
- The potentiometer will have three terminals (legs).
- Measure the resistance between the two outer legs—this should reflect the total rated resistance of the potentiometer (e.g., 5kΩ, 10kΩ, etc.).
- Leave one probe on one outer leg and move the other to the center leg (wiper).
- Slowly rotate the potentiometer through its full range.
- The resistance value on the meter should change smoothly.
- If the reading jumps erratically, the potentiometer may be dirty or damaged.
- Keep the center probe in place and move the outer probe to the opposite outer leg.
- Repeat the test as in step 6.
If the readings are inconsistent or erratic, try cleaning the potentiometer with an appropriate contact cleaner. If issues persist, replacement may be necessary.