GE Dishwasher C4 Error: How to Fix by Unsticking the... | appliancefaults.com

Technical Background:

The MCU (Main Control Unit) monitors the float switch. If the float switch indicates an overfill condition (float in the 'up' position) for an extended period, the MCU triggers the C4 error and shuts down the dishwasher. The float switch circuit typically operates on a low voltage DC signal (e.g., 5V DC) from the MCU.

Symptoms:

US homeowner observations might include the dishwasher not starting, stopping mid-cycle, or displaying a 'C4' error code on the control panel. The dishwasher may also have standing water at the bottom of the tub.

Possible Causes:

Stuck float switch due to debris.
Faulty float switch.
Defective water inlet valve leaking past its seal.
Clogged drain causing backup into the dishwasher tub.
Problem with the main control board (MCU).
Wiring harness issue affecting the float switch circuit.

Solution:

1

Disconnect power to the dishwasher at the breaker panel. Verify 0V AC at the dishwasher junction box with a multimeter.
2

Locate the float switch inside the dishwasher tub, typically at the front.
3

Inspect the float and float cup for any visible debris or obstructions. Clean as needed.
4

Manually test the float's movement. It should move freely up and down.
5

Use a multimeter to test the float switch continuity when the float is in the up and down positions. It should switch between open and closed.
6

If the float switch is faulty, replace it with a new one.
7

If the float switch tests good, suspect a faulty water inlet valve or main control board. Replace accordingly after further testing.

Safety Warning:

Always disconnect power to the dishwasher at the breaker panel before performing any repairs. Lock Out / Tag Out (LOTO) procedures should be followed to prevent accidental re-energization. High voltage is present at the dishwasher junction box.

Prevention:

Regularly clean the dishwasher's filter and inspect the float area for debris. Avoid overloading the dishwasher to prevent food particles from entering the float switch area.

Expert Tip:

Some GE dishwashers have a service mode that allows you to manually test the float switch and other components. Refer to the technical service manual for your specific model to access the service mode sequence (typically involves pressing a combination of buttons on the control panel).

Frequently Asked Questions

•How do I access the float switch on my GE dishwasher?

The float switch is typically located at the front of the dishwasher tub, often behind a small cover or panel. You may need to remove the lower spray arm and filter assembly to access it.

•What voltage should I expect to see at the float switch wiring harness?

The float switch circuit usually operates on a low DC voltage, typically 5V DC or 12V DC. Refer to the wiring diagram for your specific model.

•How do I test the water inlet valve for leakage?

Disconnect the water supply line and the electrical connector to the water inlet valve. Place a bucket under the valve and reconnect the water supply. If water leaks out of the valve with the power disconnected, it is likely faulty and needs to be replaced.

GE Dishwasher C4 Error: How to Fix by Unsticking the Float Cup

Technical Background:

Symptoms:

Possible Causes:

Solution:

Safety Warning:

Prevention:

Expert Tip:

Frequently Asked Questions

•How do I access the float switch on my GE dishwasher?

•What voltage should I expect to see at the float switch wiring harness?

•How do I test the water inlet valve for leakage?

Related questions

Technical Background:

Symptoms:

Possible Causes:

Solution:

Safety Warning:

Prevention:

Expert Tip: