Small PCB relay with its cover removed, showing the coil and switching contacts
Generic photo: Raimond Spekking · CC BY-SA 4.0

Relay on a control board: clicks but no output

A click only proves the coil moved. Burnt or pitted contacts can still fail to pass current. Measure across the contacts under load and at the output pin.

Cross-checked ~30 min advancedBrands: All

Before you start

  • Live-voltage tests: use a CAT III-rated meter, insulated probes and one hand; keep the other hand away from the chassis
  • Relay contacts often switch line voltage; never touch the board with power on
  • Unplug before resistance tests

Diagnostic steps

Unlock all 5 steps with expected values

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OnCall Tech is a reference tool for trained technicians and can make mistakes. Always disconnect power and confirm with the manufacturer's documentation before you work.

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Relay on a control board: clicks but no output · OnCall Tech