The short answer
What 4d42 tells you is that the cooling fan is turning faster than the control expects. The oven generally still cooks; what is wrong is the control's confidence in the reading. Start with a feedback signal the control misread rather than a fan that is genuinely racing rather than with a part.
The code table for this reading
Reference| Code | Documented meaning |
|---|---|
| 4d42 | Cooling fan speed too high. |
What is happening apart from the display
- The fan is noticeably louder than it used to be — A fan stuck at full speed is the version of this an owner hears.
- The code appears with no change in how the oven cooks — Unlike its opposite, this one often has no cooking symptom at all.
- NEAR MISS - the fan is loud and the cavity is also too hot — Two symptoms at once points at the temperature side rather than the fan, and that is a different page.
Causes, and why they rank that way
- A misread speed signal rather than a fast fan — Ranked first because it is the commonest and the cheapest: the tacho feedback is noisy, the fan is fine, and a power-down clears the latched reading.
- Wiring or a connector at the fan — Third: a marginal connection produces feedback the control cannot use either way.
The check order this code implies
- Power down fully and see whether the code returns — Free, and it clears a misread on its own more often than not.
- Note whether it runs on after the oven is cold — A fan that never stops is a drive fault; one that stops on time is a feedback fault.
The owner-side procedure
- Power the appliance down at the breaker and bring it back — The documented first action, and it clears a latched misread.
About 5 min
- Run a short bake and listen to the fan through the cycle — Normal-sounding with no code is finished; loud with a code is a service call.
About 25 min
- STOP HERE - the fan and its wiring sit behind the appliance — Reaching them means pulling a built-in unit out of its opening.
Before you open anything
Safety
Power off at the breaker or at the plug before any panel is removed - a capacitor can hold a charge after the power is off. The owner-side checks on this page need no panel removed at all. If you get as far as wanting a meter on something, that is the point to call rather than the point to improvise.
When this is a service call
The free checks above come first; past them this is a visit. Call if the code returns after a power-down or the fan will not stop when the oven is cold: an unregulated fan is a drive or a motor fault and both are service parts. There is no emergency in this code by itself.
Codes read alongside this one
How far this page applies
This reading is written for the built-in model lines whose control monitors fan speed in both directions, and it stays with the code in its title. What is deliberately not here: the resistance tables, wiring colours and part numbers that differ between model lines, all of which belong to the service documentation for a specific unit rather than to a page about a code. If a page exists for your exact family or model, that page is the more specific answer and it should be read first; the code index linked below is where those pages are listed.
The full code index for this appliance
Lead Appliance Repair Technician · 12 years experience
Experienced technician with 12 years specializing in washing machine and dryer repairs across all major brands.
