Code P015, Open Engine Coolant Temperature (ECT) Sensor: Action

PCM turns on MIL and uses IAT sensor value instead of ECT sensor value for all calculations during first 10 minutes of operation; PCM then uses a value of 194°F (90°C).

1. With ECT sensor or wiring open, PCM parameter PD04 should indicate -36.4°F (-38°C) or less. If PD04 does not indicate -36.4°F (-38°C) or less, ECT sensor and wiring are okay. See NOTE ON INTERMITTENTS.
2. Checks for open in circuit No. 410 from PCM to sensor. If parameter PD04 indicates 148-151°C with ECT sensor wiring harness terminals jumpered, circuits No. 410 and 808 are okay.
3. Checks for open in circuit No. 1076 from sensor terminal "A" to ground splice. If shorting terminal "A" to ground causes parameter PD04 to indicate 148-151°C, an open in circuit No. 808 exists.
4. Checks if PCM recognizes low voltage on terminal 3E16. If grounding terminal 3E16 causes PD04 to indicate 148-151°C, circuit No. 410 from PCM to ECT sensor is open.