Circuit/System Description
NOTE:
The radiator coolant temperature sensor is referred to as B34B Engine Coolant Temperature Sensor 2 in schematics and other areas.
The radiator coolant temperature (RCT) sensor is a variable resistor that measures the temperature of the engine coolant in the radiator. This diagnostic checks for an open, short to ground or an intermittent circuit condition between the engine control module (ECM) and RCT sensor.
The following table illustrates the difference between temperature, resistance and voltage:
| RCT | RCT Resistance | RCT Signal Voltage |
|---|---|---|
| Cold | High | High |
| Warm | Low | Low |