GE Dishwasher Error Code C8: Detergent Cup Blocked -... | appliancefaults.com

Technical Background:

The C8 error on a GE dishwasher indicates a problem with the detergent dispenser system. The main control unit (MCU) sends a 120V AC signal to the detergent dispenser solenoid at the appropriate time during the wash cycle. This voltage energizes the solenoid, which releases the latch holding the detergent cup door closed. A faulty solenoid, wiring issue, or malfunctioning MCU can disrupt this process, triggering the C8 error.

Symptoms:

The homeowner reports the dishwasher stopping mid-cycle. Dishes are not cleaned properly. The detergent cup is either not opening at all or is opening prematurely. A C8 error code is displayed on the control panel.

Possible Causes:

Detergent cup physically blocked by dishes or debris.
Faulty detergent dispenser solenoid.
Wiring harness issue between the control board and dispenser.
Defective main control board (MCU).
Detergent dispenser spring broken or dislodged.

Solution:

1

Unplug the dishwasher or turn off the breaker to the unit at the breaker panel.
2

Visually inspect the detergent cup area for any obstructions. Remove any visible debris.
3

Using a multimeter, test the detergent dispenser solenoid for continuity. It should typically read between 500-1500 ohms. If open, the solenoid is defective and must be replaced.
4

Inspect the wiring harness and connector to the detergent dispenser for any damage, corrosion, or loose connections. Repair or replace as needed.
5

Access the main control board (MCU). Refer to the service manual for its location. Disconnect and reconnect the wire harness to the control board to ensure a secure connection.
6

If the wiring and solenoid are good, but the C8 error persists, the main control board (MCU) may be defective. Replacement of the control board may be required. Program it if needed.
7

After repairs, run a diagnostic cycle to confirm the C8 error is resolved. Clear the error code.

Safety Warning:

Always disconnect power to the dishwasher before performing any repairs. Lock Out/Tag Out (LOTO) procedures should be followed. Some components carry 120V AC, which can cause electric shock.

Prevention:

Avoid overloading the dishwasher. Load dishes so they do not block the detergent dispenser. Regularly clean the dispenser area to prevent build-up. Use high-quality detergent and rinse aid.

Expert Tip:

Many GE dishwashers have a service mode that can be accessed by pressing a specific sequence of buttons (typically Start, then Up, then Down, then Start again within a short time frame). This mode allows you to run individual component tests, including the detergent dispenser, to further diagnose the problem.

Frequently Asked Questions

•How do I access the service mode on my GE dishwasher?

The service mode sequence varies slightly by model. Refer to the service manual or search online using your specific model number. A common sequence is Start, Up, Down, Start within 6 seconds.

•What voltage should I expect to see at the solenoid connector when the dispenser is supposed to open?

You should measure approximately 120V AC at the connector pins leading to the solenoid when the control board is signaling the dispenser to open. Use caution when testing live voltage.

•Where can I find the part number for a replacement detergent dispenser solenoid?

The part number for the solenoid is usually located on the solenoid itself. You can also find it by searching online parts retailers using your dishwasher's model number. Always double-check compatibility before ordering.

GE Dishwasher Error Code C8: Detergent Cup Blocked - Troubleshooting

Technical Background:

Symptoms:

Possible Causes:

Solution:

Safety Warning:

Prevention:

Expert Tip:

Frequently Asked Questions

•How do I access the service mode on my GE dishwasher?

•What voltage should I expect to see at the solenoid connector when the dispenser is supposed to open?

•Where can I find the part number for a replacement detergent dispenser solenoid?

Related questions

Technical Background:

Symptoms:

Possible Causes:

Solution:

Safety Warning:

Prevention:

Expert Tip: