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Whirlpool Dishwasher Diagnostic Mode: How to Enter and Read Results

Quick Answer

Whirlpool dishwasher diagnostic mode is entered by pressing any 3 non-Power buttons in an A-B-C repeating sequence (e.g., Heated Dry, Normal, Heated Dry, Normal, Heated Dry, Normal) within 8 seconds. Once entered, the control board runs through a complete test sequence: fills the tub, activates the heater, runs the wash motor, and drains.

Whirlpool dishwasher diagnostic mode is entered by pressing any 3 non-Power buttons in an A-B-C repeating sequence (e.g., Heated Dry, Normal, Heated Dry, Normal, Heated Dry, Normal) within 8 seconds. Once entered, the control board runs through a complete test sequence: fills the tub, activates the heater, runs the wash motor, and drains. Any fault that occurs during the sequence, or any code stored in memory, will be displayed. The alternate method on newer models is: hold Heated Dry and Normal simultaneously twice within 6 seconds.

WhirlpoolDishwasherSeverity: low90% DIY Success
Time to Fix
5–20 min
Difficulty
beginner
Parts Cost
—
Tools Needed
None

What Does the DIAG-MODE Code Mean?

Diagnostic mode forces a complete self-test and reveals stored fault codes. The entry sequence is the A-B-C button pattern repeated three times within 8 seconds. The sequence tests fill, heat, motor, and drain in order.

Most Likely Causes

Based on aggregated repair data, here is the probability breakdown for this error code:

Used to diagnose any error code before component testing40%
Used to verify a repair was successful after component replacement36%
Used when dishwasher behaves abnormally without displaying a code24%

Symptoms You May Notice

  • Used proactively -- no specific symptom triggers diagnostic mode
  • Dishwasher behaves abnormally but no code is displayed
  • Recently replaced a component and want to verify it works

Can you reset a Whirlpool dishwasher to clear the DIAG-MODE code?

Diagnostic mode is entered intentionally and exits automatically when the full test sequence completes. To exit early, hold Cancel/Drain for 3 seconds.

Diagnostic Checklist

Follow these steps in order. We start with the easiest external fixes before opening up the machine.

1

With the dishwasher door closed and power on

With the dishwasher door closed and power on, identify 3 buttons to use as A, B, C. Common choices: Heated Dry (A), Normal (B), and any third button (C). Do NOT use Power. Press the sequence A-B-C three times in a row within 8 seconds total.

2

Once in diagnostic mode

3

To exit diagnostic mode before completion

Frequently Asked Questions

Will entering diagnostic mode hurt my dishwasher?
No. Diagnostic mode is a factory-designed self-test feature. It runs the dishwasher through normal fill, wash, and drain sequences under controlled conditions. It can be run safely at any time.
What if my dishwasher does not accept the diagnostic mode sequence?
Some models require a specific set of buttons for the A-B-C sequence. If the standard 3-button sequence does not work, try the Heated Dry and Normal combination: press Heated Dry, then Normal, then repeat once more, all within 6 seconds. Consult the tech sheet (taped inside the door panel or downloadable by model number) for model-specific sequences.
Can diagnostic mode cause a false error code?
No. Diagnostic mode only reports codes that reflect actual hardware faults detected during the test sequence. It cannot generate a code for a component that is working correctly.

Related Whirlpool Dishwasher Error Codes

Code: RESETHow to Reset a Whirlpool Dishwasher: Every Method That WorksCode: HUBWhirlpool Dishwasher Error Codes: Complete Guide to Every Fault Code

Same Fix Works on These Brands

Whirlpool shares the same hardware platform with these brands. The diagnosis and repair steps are identical.

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Models Known to Experience DIAG-MODE Errors

This repair applies to most Whirlpool dishwashers with this error code. Common model numbers include:

WDT780SAEM, WDF550SAHZ, WDT730PAHZ, WDT750SAHZ, WDT970SAHZ, WDF518SAHM, WDT720PADE

Last verified for technical accuracy on March 14, 2026