Monogram Dishwasher C9 Error: Leak detected / water in base pan
The C9 error code on a GE Monogram dishwasher indicates that the leak detection sensor in the base pan has detected water — the same protection mechanism as the C1 code, but triggered under a different operating condition or by a distinct sensor circuit depending on model. Water has accumulated in the drip tray beneath the tub and the control board has halted operation to prevent further leakage and water damage.
~30%
DIY Fixable
From $125
Typical Repair Cost
1-3 hrs
Pro Repair Time
Quick Assessment
Answer to continue safely
Is it safe to keep using?
No. Do not run the dishwasher while C9 is active or while the leak source is unidentified. Continued use risks water damage to adjacent cabinetry, flooring, and electrical components.
Can I reset the code?
No. Cutting power for 60 seconds clears the display, but C9 returns the moment the sensor detects moisture again. The base pan must be completely dry and the leak source repaired before the reset will hold.
When to stop immediately?
Stop if you notice: Stop using the dishwasher immediately when C9 is displayed — continued leaking can cause structural water damage., Stop and call a technician if the base pan refills with water after being dried and the door gasket appears undamaged..
Symptoms You May Notice
Water is visible on the kitchen floor beneath or in front of the dishwasher toe-kick panel.
C9 fault code displayed on the control panel, cycle halted mid-operation.
Drain pump activates and runs continuously after the cycle stops in an attempt to evacuate base pan water.
Dishwasher stops filling or washing and cannot be restarted until the code is cleared and base pan is dry.
Possible Causes
Damaged or displaced door gasket allowing wash water to escape the tub during the wash or rinse phase.
DIY PossibleCracked tub, spray arm hub, or internal water fitting leaking directly into the base pan.
Requires ProfessionalLoose or degraded hose clamp on the internal drain or circulation hose allowing water to drip into the base.
Requires ProfessionalSafe Checks You Can Do
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1
Dry the base pan and inspect the door gasket
Remove the lower toe-kick panel and use dry towels to absorb all water from the base pan. Inspect the door gasket around the full perimeter for cracks, tears, or sections lifted out of their retaining channel.
Allow the base pan to dry completely before resetting — even residual moisture can re-trigger the sensor.
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2
Run a short cycle and observe
With the base pan dry and the code reset (cut power for 60 seconds), run a short rinse cycle. After it completes, remove the toe-kick panel immediately and check whether any new moisture is present in the base pan.
Watching the dishwasher from the front during the cycle may reveal water escaping around the door seal.
When to Call a Professional
Contact a qualified technician if:
- The door gasket is undamaged and properly seated, but the base pan fills with water on every cycle, indicating an internal hose or fitting failure.
- C9 persists on a completely dry base pan, suggesting a faulty leak sensor that requires professional replacement.
Need Professional Help?
Find qualified technicians in your area for proper diagnostics and repair.
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