Samsung Mini-Split E1-01 Error Code — What It Means
E1-01 on a Samsung mini-split (Wind-Free, AR series, and multi-zone systems) indicates an outdoor air temperature sensor fault. The control board is receiving a signal from the outdoor ambient temperature sensor that is outside the valid range — either an open circuit (sensor disconnected or broken) or a short circuit (sensor shorted). Samsung uses thermistor-type temperature sensors; the board compares the sensor resistance to a known curve and flags E1-01 when the reading is invalid.
Common Causes
- Failed outdoor temperature sensor (thermistor) — The sensor element degrades over time, especially with UV exposure, moisture, or vibration on the outdoor unit. Open or shorted thermistors produce out-of-range readings.
- Loose or corroded sensor connector — The plug connecting the sensor wire to the outdoor control board can corrode or vibrate loose, breaking the circuit.
- Damaged sensor wire — Rodent damage, pinching by a panel edge, or UV degradation of wire insulation can break or short the sensor circuit.
- Failed outdoor control board — Rarely, the sensor input circuit on the board itself fails, causing false E1-01 readings even with a good sensor.
Step-by-Step Fix
- Locate the outdoor temperature sensor — On Samsung outdoor units, the ambient temperature sensor is typically clipped to the intake area of the outdoor coil or mounted near the top of the outdoor unit chassis. It is a small probe with a 2-wire lead.
- Inspect the sensor and connector — With power off, check the sensor connector on the outdoor control board for corrosion, bent pins, or a loose fit. Reseat the connector firmly.
- Test sensor resistance — Disconnect the sensor from the board. Using a multimeter on resistance (ohms) mode, measure across the sensor leads. At room temperature (20–25°C), most Samsung thermistors read approximately 10–12 kΩ. Open circuit (OL) or near-zero (short) = replace the sensor.
- Inspect the sensor wire — Trace the wire from the sensor to the board. Look for pinched, chewed, or cracked insulation. Repair or replace if damaged.
- Clear the fault and test — After replacing the sensor or reseating the connector, restore power and power cycle the outdoor unit. Verify E1-01 does not return.
Parts Often Needed
| Part | Notes |
|---|---|
| Outdoor ambient temperature sensor | Samsung OEM; 10 kΩ NTC thermistor; match connector |
| Sensor harness/extension wire | If wire run is damaged |
| Outdoor control board | Only if sensor input circuit is confirmed failed on the board |
Need Replacement Parts?
Finding the right replacement parts for your equipment is critical to getting it running again. Check current prices on Amazon — prices and availability change frequently.
When to Call a Pro
If sensor and wiring check out but E1-01 persists, the outdoor control board’s sensor input circuit may need component-level repair or board replacement. A Samsung-authorized technician can access fault logs and confirm the board diagnosis.