Whirlpool Dishwasher Clean Light Blinking 8 Times: Drain... | appliancefaults.com

Technical Background:

The dishwasher's Main Control Unit (MCU) monitors the drain pump circuit. The MCU sends a 120V AC signal to the drain pump relay on the control board, which then powers the drain pump. If the MCU detects an open or shorted circuit, or the pump is not running as expected, it will trigger the fault code (8 blinks).

Symptoms:

The homeowner observes the clean light blinking 8 times on their Whirlpool dishwasher. The dishwasher may not be draining properly, or at all, and may be making unusual noises.

Possible Causes:

Drain pump failure
Blocked drain hose
Clogged drain impeller
Faulty drain pump relay on the control board
Wiring harness issue between the control board and drain pump
Defective pressure switch

Solution:

1

Disconnect power to the dishwasher at the breaker panel. Verify 120V AC is OFF using a multimeter.
2

Locate the drain pump, typically at the bottom of the dishwasher. It is often accessible from the front after removing the lower access panel.
3

Inspect the drain hose for kinks or obstructions. Remove the hose and flush with water.
4

Access the drain pump and check for debris blocking the impeller. Remove any obstructions.
5

Use a multimeter to test the drain pump windings for continuity. Disconnect the drain pump wires first. A reading of OL (open line) indicates a failed pump. A typical resistance reading should be between 20-100 ohms.
6

If the pump checks out, inspect the wiring harness between the control board and the drain pump for damage. Check for loose connections or frayed wires.
7

Replace the drain pump if it's faulty. If the wiring is damaged, repair or replace it. If all else fails, the control board might be faulty and need replacement.

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. High voltage is present inside the appliance. Wear appropriate safety gear.

Prevention:

Regularly run a dishwasher cleaner to prevent buildup and clogs. Check and clean the drain filter periodically.

Expert Tip:

Enter service mode by pressing and holding the High Temp Scrub and Heated Dry buttons for 5 seconds. This allows you to run diagnostic cycles and further isolate the issue. You can manually activate the drain pump in service mode to test if it is working at all.

Follow-up Questions:

Frequently Asked Questions

•How do I access the drain pump on my Whirlpool dishwasher?

Typically, you need to remove the lower access panel, often held in place by screws. The drain pump is usually located at the bottom of the dishwasher tub.

•What resistance reading should I expect from a functioning drain pump?

A functioning drain pump typically has a resistance between 20 and 100 ohms. However, this can vary slightly depending on the specific model. Always consult the service manual if available.

•Where is the control board located, and how difficult is it to replace?

The control board is usually located behind the control panel on the top of the dishwasher door. Replacement involves removing the control panel, disconnecting the wiring harness, and installing the new board. It's moderately difficult, requiring basic hand tools and attention to detail.

Whirlpool Dishwasher Clean Light Blinking 8 Times: Drain Pump Circuit Fault Troubleshooting

Technical Background:

Symptoms:

Possible Causes:

Solution:

Safety Warning:

Prevention:

Expert Tip:

Frequently Asked Questions

•How do I access the drain pump on my Whirlpool dishwasher?

•What resistance reading should I expect from a functioning drain pump?

•Where is the control board located, and how difficult is it to replace?

Related questions

Technical Background:

Symptoms:

Possible Causes:

Solution:

Safety Warning:

Prevention:

Expert Tip: