General Information
Component Location
General Description
A water temp sensor located at heater unit detects coolant temperature. It contains negative type themistor whose resistance value is in inverse proportion to temperature. Resistance of watersensor that varies with temperature makes signal voltage of A/C ECU change. In this way A/C ECU detects temperature. Signal of water sensor is used for cold engine lockout control-When the driver operates the heater before the engine is warmed up enough, to prevent driver from unpleasantness of cold air. the heater control unit reduces blower motor speed until coolant temperature reaches the threshold value.
DTC Description
Air conditioner Control Module sets DTC B1202 if water temperature sensor has been detected over 4.9V for 4 seconds.
DTC Detecting Condition
Specification
** Resistance value of Water temperature sensor as a function of temperature.
Diagnostic Circuit Diagram