Pcm Code P015 - Open Coolant Sensor Signal: Notes
Coolant sensor is a 2-wire thermistor, whose resistance varies with temperature. Sensor signal is on circuit No. 410; sensor ground is on circuit No. 1076.
As sensor temperature increases, sensor resistance decreases. High coolant temperature will result in low signal voltage on circuit No. 410. PCM Code P015 sets because PCM assumes coolant temperature cannot be -36°F (-38°C) or less when IAT is 4.4°F (-20°C) or greater.