KitchenAid dishwasher 4-2: wash motor: motor communication error
4-2 means the signals between the main control and the wash motor's own electronics were garbled or interrupted.
What 4-2 means
- Brand
- KitchenAid
- Appliance
- Dishwasher
- Code
- 4-2
- Documented meaning
- Wash motor: motor communication error
- Applies to
- 31 KitchenAid models on 1 platform
- Can you keep using it?
- With caution
What the dishwasher is detecting
The control and the wash motor exchange messages while the motor runs. Errors in that exchange, as opposed to no reply at all, set this code.
Causes listed for this condition
In the order the service documentation checks them. Documented causes come from the manufacturer's service documentation for these platforms; possible causes are based on how the system works; unconfirmed marks common assumptions that the documentation does not support.
- Documented A communication error between the control and the motor, often from a poor connection at either end.
- Documented A failing wash motor; the documentation has the technician try the motor before the control.
- Possible A main control fault.
Safe checks you can make
- Switch off the dishwasher's circuit breaker (or unplug it, if it plugs in under the sink) for one minute, restore power and run a short cycle to see whether the code returns.
- Note whether the code comes back right after a power reset or only after some cycles; that detail helps the technician.
Further diagnosis requires opening the appliance. Beyond the owner checks, diagnosis involves removing panels, testing components and checking wiring. We describe what a technician investigates, not how to do it yourself.
What a technician checks
- Checks the connections at the motor and at the control.
- Rechecks motor operation in service diagnostics after reconnecting.
- Follows the documented order of suspecting the motor before the control.
Typical repairs and cost
Depending on what diagnosis finds, this code can lead to one of these repairs:
| Repair | Typical range | Labor |
|---|---|---|
| Dishwasher circulation pump and wash motor replacement | $300–$620 | Heavy |
| Dishwasher main control board replacement | $260–$590 | Moderate |
Typical total ranges for the Las Vegas area, parts and labor included. The final cost depends on diagnosis, the exact model, parts availability and whether other damage is found.
Can you keep using it?
Use with caution. Washing may be weak or stop mid-cycle. Schedule service if the code repeats.
KitchenAid models documented with this code
And 26 more. Use the model lookup to check yours.
Related problems and codes
Other codes documented on the same KitchenAid platforms:
Repair or replace?
A fault code alone rarely justifies replacing a dishwasher. Most 4-2 repairs involve a single component once diagnosed. Replacement becomes worth considering when the unit is near the end of its typical 9–12-year life and the diagnosed repair is a major one. See the repair-or-replace guide.
Need 4-2 diagnosed in the Las Vegas area?
We repair Whirlpool, Maytag, KitchenAid, JennAir, Amana and other Whirlpool-family appliances in Las Vegas, Henderson, Summerlin and Boulder City. A model number helps but is never required to book.