Drain pump removed from a washing machine
Generic photo: Poo (Wikimedia Commons user) · Public Domain

How to test a drain pump (washer and dishwasher)

Most drain pumps are small synchronous motors. Clear the filter and impeller first, then test the winding and the voltage. Published resistance values vary a lot by brand, so use the tech sheet for the number.

Cross-checked ~40 min moderateBrands: All

Before you start

  • Unplug the appliance or turn off the breaker before opening panels or disconnecting parts
  • Take a photo of the wiring before removing any wire
  • Resistance and continuity tests are done with power OFF and the part isolated
  • Live-voltage checks are a caution step: insulated probes, one hand, clips attached before power is restored, stay clear of terminals
  • Expect water when you open the filter or hoses

Diagnostic steps

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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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