B0161

Schematic:

CIRCUIT DESCRIPTION
The Outside Air Temperature Sensor is located on driver side front grille. In this position it is exposed at airflow throw the grill. This provides a sample of the outside (ambient) air temperature. The sensor is a thermistor used to control signal voltage to the heater and A/C control. A/C control supplies a reference voltage (-5 V) to the sensor and measures voltage drop in the circuit to obtain a temperature signal. This signal is an input that tells the heater and A/C control how much cooling or heating will be required for passenger compartment. It also affects mode and blower speed.

When the outside (ambient) air temperature is cold, thermistor resistance is high; therefore heater and A/C control will receive a high signal voltage input. If air temperature is hot and thermistor resistance is low, heater and A/C control will receive a low signal voltage input.

DTC PARAMETERS
^ Ignition in RUN position
^ YEL (Circuit 61) shorted to battery voltage
^ Condition is present for 30 seconds
^ Counts are higher than 252

DIAGNOSTIC AIDS
If DTC in history or an intermittent condition, perform the test shown by wiggling wiring and connectors. This will cause malfunction to appear.

Visually inspect sensor connector and harness for damage, corrosion or water intrusion.

Check connector halves for poor mating or terminal not fully seated in the connector body (backed out).

Check for adequate terminal tension, mis-routed harness, rubbed-through wire insulation and broken wire inside the insulation.

Check for improperly formed or damaged terminals. All connector terminals in the related circuit should be carefully reformed or replaced to ensure proper contact tension.

TEST

Diagnostic Chart: