Washer-dryer combo overfills, water level too high, or unit stops with E04 displayed; may also trigger a drain pump run without washing.

Safety first: Disconnect power and turn off water supply before opening the cabinet.

Step-by-step checks:

• 1. Locate the pressure sensor: Remove the top panel of the Monogram combo. The pressure sensor is typically a small round or rectangular device with a thin rubber hose attached and a wiring connector.
• 2. Inspect the pressure hose: Follow the hose from the sensor down to the tub or air dome. Check for kinks, cracks, or disconnections. Remove the hose and blow through it to ensure it is clear.
• 3. Clean the air dome/tub port: Where the hose connects to the tub, check for detergent residue or lint buildup. Carefully clear any blockage so air can move freely.
• 4. Check electrical connections: Reseat the wiring connector at the pressure sensor and inspect for corrosion or bent pins. Follow the harness to the main control board and ensure it is not pinched or damaged.
• 5. Test or replace the sensor: If available, run the unit's diagnostic mode per the service manual to read water level sensor values. If readings are erratic or out of range, replace the OEM Monogram water level/pressure sensor.
• 6. Reassemble and test: Reinstall the top panel, restore power and water, and run a small load to verify proper fill level and that E04 does not reappear.

When to call a technician: Persistent E04 after hose and sensor replacement may indicate a defective main control board, which should be evaluated by a professional.