Electric drive motor removed from a washing machine

Generic photo: Poo (Wikimedia Commons user) · Public Domain

How to test a universal (brushed) motor and its carbon brushes

Universal motors run on AC or DC through carbon brushes that rub on a commutator. Brushes wear out and are the most common failure. Check brush length and the commutator, then test the field and armature with a meter.

Cross-checked ~60 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

Diagnostic steps

Unlock all 6 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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