Inside a worn garbage disposal: rusty grinding plate and lugs seen from the sink

Sink water backs up into dishwasher

The dishwasher drain needs a high loop or air gap and must connect above the disposal. A clogged disposal or trap also pushes water back.

Cross-checked ~30 min easyBrands: All

Before you start

Turn off power at the breaker or unplug before reaching into or under the disposal
Never put hands in the grinding chamber; use the hex wrench or tongs

Diagnostic steps

Unlock all 3 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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