P0118 – Engine Coolant Temperature (ECT) Circuit High Input
Indicates the sensor
signal is greater than Self-Test maximum. The ECT sensor maximum is 4.6 volts or -50°C (-46° F).
Note on some vehicles that are not equipped with an ECT sensor, CHT can be used and can set this DTC.
● ● Open circuit in harness
● Sensor signal short to power
● Damaged PCM
● Improper harness connection
● Damaged sensor
■ Using signal simulation,
disconnect sensor and simulate 1.0V on sensor signal circuit. Simulated 1.0V signal and scan PID voltage value should be similar. If voltage is similar check sensor, if voltage is not similar check related circuit and PCM.