KitchenAid Combination Microwave Code F4 E6: Wave guide temperature sensor reading is off

What F4 E6 means

KitchenAid combination microwave-wall ovens such as the KOCE500ESS display F4 E6 when the wave guide temperature sensor, or the wiring serving it, may have a problem. The wave guide carries microwave energy into the cavity, so the control monitors its temperature closely. A bad reading triggers the code and halts the microwave half of the oven. Wait for the unit to cool before you test again.

Common causes of F4 E6

Wave guide temperature sensor reporting an invalid reading
Loose, pinched or damaged wiring to that sensor

✓ One safe check you can try

1. Press Cancel and wait a few minutes so the unit can cool down. 2. Check that the cavity is empty and clean, with no foil or metal inside. 3. Switch power off at the breaker for one minute, then back on. 4. If F4 E6 returns on a short test, stop and call us.

! Why to stop there

The wave guide sits right beside the high-voltage section, a zone where DIY work is never safe.
Only a measurement tells a failing sensor from a wiring issue.
We explain the cause in plain language and quote in writing before we start.

Opening a panel yourself does not automatically cancel a manufacturer warranty, but it can cause accidental damage, and some manufacturers set their own service conditions. Check your warranty terms, or ask us, before deciding.

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Other Microwave codes

Registration ErrorKitchenAid Over-the-Range Microwave Message "Registration Error": Check the home network and try again Sabbath, Sab, 5Ab, or 5A6KitchenAid Built-In Microwave Display Sabbath, Sab, 5Ab or 5A6: Sabbath Mode is on SEKitchenAid Over-the-Range Microwave Code SE: Keypad or user interface problem Probe or Insert ProbeKitchenAid Combination Microwave Message "Probe" or "Insert Probe": Seat the meat probe in its jack PUSH or PSHKitchenAid Built-In Microwave Message PUSH or PSH: The oven is waiting for Start F4E9KitchenAid Over-the-Range Microwave Code F4E9: Smart Pop control or wiring flagged FC E1KitchenAid Over-the-Range Microwave Code FC E1: Wi-Fi link timed out F6KitchenAid Over-the-Range Microwave Code F6: Relay control board

F4 E6F4 E6 questions

Is the wave guide part dangerous?

It sits in the high-voltage microwave section, which is why we keep owners out of the cabinet. All you need to do is reset power and report whether the code comes back.

Did overheating cause F4 E6?

The code points at the sensor that measures wave guide temperature, not a confirmed overheat. A cool-down and a reset are reasonable first moves, but a repeat needs a visit.

Does the lower oven stay usable?

Often yes. The code is specific to the microwave cavity, and the lower oven may keep working unless the display shows additional messages. Keep any other display messages in mind and mention them when you call.