Samsung Air Conditioner Error Code E315

Error code E315 on a Samsung air conditioner indicates a high pressure sensor fault, specifically an OPEN or SHORT condition detected in the high pressure sensor circuit. This fault is evaluated when the compressor is preparing to operate. The control board monitors the signal voltage from the high pressure sensor continuously during this window, and if the voltage falls below 0.4V, the system classifies the fault as a SHORT. If the voltage rises above 4.2V, the system classifies it as an OPEN. Both conditions tell the controller that the sensor signal is outside the valid operating range, which prevents accurate refrigerant pressure monitoring.

The high pressure sensor is a critical safety component in the refrigerant circuit. It measures pressure on the discharge side of the compressor and sends a proportional voltage signal back to the main control board. When this signal is lost or corrupted due to a wiring fault, failed sensor, or connector issue, the system cannot confirm that refrigerant pressures are within safe limits. As a safety measure, the unit will not allow normal compressor operation to proceed under these conditions.

Importantly, the E315 detection is intentionally bypassed during oil recovery, safety start, and defrost operations. This means technicians should not attempt to diagnose the fault while any of these routines are active, as the system is designed to ignore sensor readings during those cycles. Diagnosis should begin with a thorough inspection of the sensor wiring harness and connector, checking for damaged insulation, corroded terminals, or loose connections before moving on to sensor replacement or control board evaluation.