KitchenAid Dishwasher Error Code 7-2: Heating Element... | appliancefaults.com

Technical Background:

The dishwasher's Main Control Unit (MCU) monitors the temperature sensor and controls the heating element via a relay or triac on the electronic control board. The MCU signals the relay to open and close, switching 120V AC power to the heating element. Error 7-2 indicates the MCU is signaling the element to turn off, but the temperature sensor reports continued heating.

Symptoms:

The homeowner notices the dishwasher is excessively hot inside, even after the cycle is complete. Error code 7-2 appears on the control panel. Food may be overcooked or scorched. Steam is excessive when the door is opened.

Possible Causes:

Stuck heating element relay on the control board.
Triac failure on the electronic control board.
Shorted heating element.
Wiring harness fault causing voltage leak to the element.
Faulty temperature sensor misreporting temperature to the control board.

Solution:

1

Disconnect power to the dishwasher at the breaker panel. Verify 0V AC at the dishwasher power cord.
2

Locate the electronic control board, usually behind the kick panel at the bottom front of the unit. Use a 1/4-inch nut driver to remove the kick panel screws.
3

Visually inspect the control board for burned or damaged components, especially around the heating element relay.
4

Using a multimeter, test the heating element relay for continuity when it should be open. A reading of near 0 ohms indicates a stuck relay.
5

Check the heating element for a short to ground using a multimeter. Resistance to ground should be infinite. Disconnect the element wires first.
6

Inspect the wiring harness between the control board and the heating element for any signs of damage or corrosion. Repair any damaged wires using properly sized wire connectors.
7

If the control board appears faulty, replace it with a new, OEM KitchenAid control board. Reprogram the board if necessary following the manufacturer's instructions.

Safety Warning:

Always disconnect power to the dishwasher at the breaker panel before performing any repairs. Lock Out/Tag Out (LOTO) procedures must be followed. The dishwasher operates on 120V AC, which can cause serious injury or death.

Prevention:

Run the dishwasher regularly to prevent corrosion. Use a dishwasher cleaner monthly. Check the spray arms for clogs regularly.

Expert Tip:

Some KitchenAid dishwashers have a service mode. Press the following sequence: High Temp, Air Dry, High Temp, Air Dry. This can allow you to run diagnostics and isolate components.

Frequently Asked Questions

•Where is the heating element located in this dishwasher model?

The heating element is typically located at the bottom of the dishwasher tub, underneath the lower spray arm. It's often a metal coil or a sheathed element.

•How do I know if the temperature sensor is faulty?

You can test the temperature sensor's resistance using a multimeter. Compare the resistance reading to the manufacturer's specifications at a known temperature (usually room temperature). A significant deviation indicates a faulty sensor.

•What is the proper way to reprogram a new control board?

Reprogramming procedures vary by model. Typically, you'll need to enter a diagnostic mode and follow the prompts on the control panel or use a specialized programming tool. Consult the dishwasher's service manual or the control board manufacturer's instructions.

KitchenAid Dishwasher Error Code 7-2: Heating Element Stays On - Troubleshooting

Technical Background:

Symptoms:

Possible Causes:

Solution:

Safety Warning:

Prevention:

Expert Tip:

Frequently Asked Questions

•Where is the heating element located in this dishwasher model?

•How do I know if the temperature sensor is faulty?

•What is the proper way to reprogram a new control board?

Related questions

Technical Background:

Symptoms:

Possible Causes:

Solution:

Safety Warning:

Prevention:

Expert Tip: