Display shows E3 and the ambient temperature reading is incorrect or the unit runs at the wrong times.

Safety: Unplug the wine cooler before removing any covers or panels.

• Locate the ambient sensor: On Blastcool outdoor and indoor models, the ambient sensor is usually behind a small grill near the front kick plate or in the rear service area where it can sense room temperature.
• Visual inspection: Check that the sensor is not touching hot components (compressor, condenser) and is not blocked by dust or debris. Clean the area with a soft brush or vacuum.
• Check wiring and connector: Trace the sensor cable back to the main PCB. Ensure the plug is fully seated and there are no signs of corrosion or rodent damage.
• Test resistance: With power disconnected, unplug the sensor and measure its resistance. Compare to the expected NTC curve at room temperature. Replace if readings are out of range.
• Replace sensor if needed: Install a new Blastcool ambient NTC temperature sensor, routing the cable away from hot or moving parts. Secure it in the original sensing location.
• Re-test: Restore power and verify that the ambient temperature displayed is close to actual room temperature and that E3 is cleared.

Persistent E3 after sensor replacement points to a defective main control PCB that should be checked by a technician.