The short answer
4d42 is a fan speed reading out of range on the high side. Because a fan cannot easily exceed its own design speed, 4d42 points at the signal path - the sense wire, the connector or the control input - far more often than at the motor itself.
This code and its neighbours on this appliance
Reference| Code | Meaning |
|---|---|
| 4d42 | Cooling fan speed too high. |
| 4d41 | Cooling fan speed too high. |
| 4d51 | There may be a problem with the Oven Door Latch Assembly, the Door Switch, or the associated wiring. |
What you see alongside the code
- The fan sounds normal but the code appears anyway — The single most telling observation on this code, and it points straight at the sense path rather than the motor.
- The code appears at start-up before any real load — A signal fault shows immediately; a thermal one would not.
- The fan note rises and falls unpredictably — A wheel loose on its shaft behaves this way and can read fast to the control.
- NEAR MISS - the fan is silent and the code is showing — No rotation at all is a different fault and a different check.
The causes, likeliest first
- A fault in the speed-sense signal path — Ranked first because a fan physically cannot run far above its design speed, so an impossible reading is almost always an impossible signal.
- A fan wheel loose on the motor shaft — The motor turns, the wheel does not follow properly, and what the control counts stops matching what the air is doing.
- A failed sense input on the control board — The counting circuit sits on the board, and when it fails the fan is healthy and the code stands.
Check in this order, and why
- Listen to the fan and judge whether it sounds normal — A normal-sounding fan with a high-speed code is the strongest single clue there is, and it costs nothing.
- Note whether the code is present at start-up — Immediate presence rules out thermal causes entirely.
- Establish whether any repair preceded it — A disturbed harness or a replaced part explains this code better than wear does.
The owner-safe procedure
- Run a short bake and listen carefully to the fan — You are deciding one thing: does it sound normal. Everything after this depends on that answer.
About 15 min
- Switch off at the breaker for several minutes and restore — A clean reset clears a one-off mis-count and tells you whether the fault is persistent.
About 8 min
- Clear and vacuum the accessible vent slots — It will not fix this code, but it removes a variable before anyone else looks at it.
Tools: vacuumAbout 12 min
Before you open anything
Safety
Unplug the appliance or switch off its breaker before removing any panel - a capacitor can hold a charge after the power is off. Do not run the oven for long cycles while its cooling protection is reporting an impossible value: the control cannot tell you whether the fan is working, and that is the whole function the reading serves. Photograph every connector before it is unplugged. A connector refitted one position out causes a second fault that looks nothing like the first.
When this is a service call
Call when the fan sounds normal and the code persists, which is the usual presentation - that combination means the signal path rather than the fan, and tracing it needs a meter on a live line. Call immediately if the fan area rattles or vibrates, because a loose wheel can damage the housing around it. Ask for the failed component to be shown to you. It is the simplest guard against a part being replaced on suspicion.
Neighbouring codes on this appliance
What this page does not cover
Read this as generalized information. It is written for 4d42 as the KitchenAid oven code list documents it across the brand rather than for one family or model line. Where a family- or model-specific page exists for your unit it is the more specific answer and is linked from the code index for this appliance. Some of the codes listed beside it in the table above carry the same documented meaning on this platform and some are documented differently, so check the characters on your display carefully before acting on this page.
Lead Appliance Repair Technician · 12 years experience
Experienced technician with 12 years specializing in washing machine and dryer repairs across all major brands.
