DTC P18A3-00: Coupling Component Temperature Sensor - High Input: Outline

WARNING: This page is about a different car, the 2020 Mazda CX-30. However, it is still accessible from the selected car via links, so may be relevant.

DTC P18A3:00 (PCM, SKYACTIV-G) DETECTION CONDITION AND POSSIBLE CAUSE

System malfunction location	Coupling component temperature sensor: High input
Detection condition	The PCM detects an open circuit or short to power supply in the coupling component temperature sensor signal circuit.
Fail-safe	Inhibits the i-ACTIV AWD control.
Possible cause	Coupling component temperature sensor connector or terminals malfunction Coupling component temperature sensor malfunction Electrical supply unit (ESU) connector or terminals malfunction Short to power supply in any of the following coupling component temperature sensor circuits. Signal circuit Ground circuit Open circuit in any of the following coupling component temperature sensor circuits. Signal circuit Ground circuit Electrical supply unit (ESU) malfunction PCM malfunction
Courtesy of MAZDA MOTORS CORP.