Built-in dishwasher with the door open and racks pulled out

Generic photo: Castorly Stock · Pexels License

Dishwasher detergent dispenser won't open (detergent left in the cup)

First rule out blocking dishes, caked detergent and an unfinished cycle. Then test the dispenser actuator (a wax motor or bimetal/solenoid on most units) for an open circuit, and check whether the control sends 120 V to it during the wash. A cup that opens but leaves detergent behind is a wash problem, not a dispenser problem.

Single source ~45 min moderateBrands: All

Before you start

Breaker off before removing the outer door panel
The live voltage check at the dispenser is caution work: keep hands clear and use insulated probes
Keep the door latched only as needed for the live test; the door switch must stay in the circuit

Diagnostic steps

Unlock all 8 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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