Volvo: engine light on, mass air flow, engine coolant temperature

Question
engine light on codes is p0118 ect circuit high input anyone nows what is that? thanks

Answer
Dennis,
Condition Engine coolant temp sensor
if the temperature sensor in the Mass Air Flow (MAF) sensor is OK, its value is used as the start temperature. Otherwise the value is set at +20°C
after starting, the Engine Coolant Temperature (ECT) is calculated theoretically
engine cooling fan (FC) at low-speed.

Possible source

Signal too high
short-circuit to supply voltage in the signal cable
open-circuit in the signal cable
defective Engine Coolant Temperature (ECT) sensor.

Signal too low
short-circuit to ground in the signal cable
defective Engine Coolant Temperature (ECT) sensor.

Condition
difficult to start when the engine is warm
driveability problems when warm starting
the engine cooling fan (FC) operates constantly.