Common Problems

• Scratchy or noisy output
• Dead spots (no change in value)
• Intermittent signal
• No output at all
• Incorrect resistance value

1. Scratchy Noise When Turning

Cause:

• Dust or dirt inside potentiometer
• Worn carbon track

Solution:

• Clean using contact cleaner spray
• Rotate knob multiple times
• Replace if noise persists

2. Dead Spots

Cause:

• Damaged resistive track
• Wiper not making proper contact

Solution:

• Test with multimeter
• Replace potentiometer

3. No Output

Cause:

• Incorrect wiring
• Broken internal connection

Solution:

• Check wiring (3-pin configuration)
• Measure continuity

4. Sudden Jumps in Value

Cause:

• Loose wiper contact
• Mechanical wear

Solution:

• Clean or replace potentiometer

Testing a Potentiometer

• Use a multimeter in resistance mode
• Measure between outer pins → fixed value
• Measure between wiper and ends → variable value

Quick Diagnostic Tip

If voltage does not change at the wiper, the potentiometer is faulty or wired incorrectly.

Preventive Maintenance

• Avoid dust exposure
• Do not overload with high current
• Use correct type (linear/log)
• Turn gently to avoid mechanical damage

When to Replace

• Persistent noise after cleaning
• Broken shaft or loose knob
• Irregular or unstable output

Common Mistakes

• Using low-power pot in high-current circuit
• Wrong wiring (middle pin ignored)
• Using linear pot for audio volume