E4

Hisense Cavity Temperature Sensor / Thermistor Fault

Microwave displays E4 and does not heat or stops mid-cycle.

Safety Warning

This repair may involve working with high voltage components or water connections. Always unplug the appliance before removing any panels.

If you are not confident in your ability to perform this repair safely, we strongly recommend contacting a professional technician.

Possible Causes

Open or shorted cavity thermistor,Loose thermistor wiring harness,Failed main control PCB temperature input circuit,Overheated cavity due to blocked vents

How to Fix / Troubleshooting

Safety first: Unplug the microwave before inspection. Do not access internal components unless qualified.

Steps you can take:

Check ventilation: Ensure that the top, sides, and rear vents are not blocked. Remove any items stored on top of the microwave that may trap heat.
Allow cooling time: If the error appears after heavy use, leave the door open and allow the unit to cool for 30–60 minutes, then try again.
Power cycle: Unplug for 5–10 minutes, then reconnect and test. Sometimes a temporary sensor reading error can be cleared.

Technician actions:

Access the oven cavity sensor (thermistor) usually mounted on the side or top of the cavity.
Test the thermistor resistance at room temperature and compare to Hisense specifications.
Inspect and reseat the sensor harness at the main control PCB.
Replace the cavity thermistor or main control PCB if readings are out of range.

Repair Difficulty

Hard 4/5

Required Part

Cavity Temperature Sensor (Thermistor)

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