Bosch Refrigerator Error Code E02 — Freezer Compartment Temperature Sensor Fault
What this means
The E02 error code on Bosch refrigerators indicates that the freezer compartment temperature sensor (NTC thermistor) has failed or is reading incorrectly. This sensor tells the control board the current freezer temperature so it can cycle the compressor on and off to maintain the set temperature. When this sensor fails, the freezer may run non-stop (causing excessive frost buildup), not run at all (causing thawing), or cycle irregularly. Food in the freezer may partially thaw or develop freezer burn.
Alternate codes: E2
Step-by-step fix
4 stepsPower-reset the refrigerator
Unplug the refrigerator or switch off the circuit breaker for 30 seconds. Restore power and wait 5 minutes to see if the E02 error clears. If it returns, proceed to testing the sensor.
Move frozen food to a cooler or insulated bags while working to prevent thawing during the repair.
Access the freezer temperature sensor
Open the freezer compartment and remove the shelves and drawers. Unscrew the rear wall panel inside the freezer to expose the evaporator area. The temperature sensor is a small probe clipped near the evaporator coils, connected by a two-wire harness.
You may encounter frost on the rear panel — this is normal. Use a hairdryer on low heat to soften any ice holding the panel screws.
Test the sensor with a multimeter
Disconnect the sensor wire connector. At freezer temperature (approximately -18°C/0°F), the NTC sensor should read roughly 15,000–20,000 ohms. At room temperature, it should read approximately 5,000–10,000 ohms. If it reads open (infinite) or zero, the sensor has failed.
Let the sensor warm to room temperature before testing if the freezer was running. A cold sensor will read higher ohms, which is normal.
Replace the freezer sensor
Unclip the faulty sensor from its mounting bracket. Route the new sensor wire through the same path and clip it into position at the same location near the evaporator. Reconnect the harness, reassemble the rear panel, replace the shelves, and restore power.
Ensure the sensor probe is positioned in the airflow path, not touching the evaporator coils directly, for accurate readings.
When to call a professional
If the sensor tests good but the freezer temperature is still unregulated, the problem may be with the compressor relay, the evaporator fan motor, or the main control board — all of which require professional diagnosis.
Related error codes
Information compiled from manufacturer service manuals, official troubleshooting documentation, and appliance repair industry resources. This guide is for informational purposes only — always consult a qualified technician for complex repairs.
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