Dodge Caliber. Manual - part 380
SENSOR-AMBIENT TEMPERATURE
DESCRIPTION
The ambient temperature sensor is a variable resistor
type sensor. It is mounted to the lower front fascia
behind the radiator grille and in front of the engine
compartment.
The ambient temperature sensor cannot be adjusted
or repaired and, if inoperative or damaged, it must be
replaced.
OPERATION
The ambient temperature sensor is a variable resistor that operates on a five-volt reference signal. The resistance
in the sensor changes as temperature changes, changing the temperature sensor signal circuit voltage to the Totally
Integrated Power Module (TIPM). Based upon the resistance in the sensor, the instrument cluster or Cab Compart-
ment Node (CCN) display senses a specific voltage on the Controller Area Network (CAN) data bus circuit, which
corresponds to a specific temperature. The compass/temperature display unit then displays the proper ambient tem-
perature.
DIAGNOSIS AND TESTING
AMBIENT TEMPERATURE SENSOR
The thermometer function is supported by the ambient temperature sensor, the Totally Integrated Power Module
(TIPM), the Controller Area Network (CAN) data bus circuit, and the instrument cluster or Cab Compartment Node
(CCN) compass/temperature display unit.
If the display shows “OC” (-49° F (-45° C)) or “SC” (140° F (60° C)), there is an OPEN or SHORT CIRCUIT that
must be repaired.
The ambient temperature sensor circuit can also be diagnosed using the following Sensor Test, and Sensor Circuit
Test. If the temperature sensor and circuit are confirmed to be OK, but the temperature display is inoperative or
incorrect, replace the instrument cluster or CCN assembly.
SENSOR TESTING
1. Turn the ignition switch to the OFF position. Disconnect and isolate the battery negative cable.
2. Disconnect the ambient temperature sensor wire harness connector.
3. Measure the resistance of the ambient temperature sensor. At room temperature (approx. 68°F (20° C)), the
sensor resistance should be between 9-11 Kilohms (9000-11000 ohms). The sensor resistance should read
between these two values. If OK, refer to the appropriate diagnostic information to continue diagnosis of the
Totally Integrated Power Module (TIPM), the Controller Area Network (CAN) data bus circuit, and the instrument
cluster or CCN. If not OK, replace the inoperative ambient temperature sensor.
REMOVAL
1. Disconnect and isolate the battery negative cable.
2. Remove the belly pan, (Refer to 23 - BODY/EXTERIOR/BELLY PAN - REMOVAL).
PM
MESSAGE SYSTEMS
8M - 17