GM Service Manual Online
For 1990-2009 cars only

Circuit Description

The driver information center (DIC) monitors the signal circuit of the ambient air temperature sensor. The ambient air temperature sensor is a thermistor which varies in resistance as the temperature changes. As the resistance of the ambient air temperature sensor increases, the DIC senses a larger voltage drop across the sensor, indicating a lower temperature. As the resistance of the ambient air temperature sensor decreases, the DIC senses a small voltage drop across the sensor, indicating a higher temperature.

Conditions for Running the DTC

The DIC must be fully operational within a continuous voltage supply of 9.0-16.0 volts.

Conditions for Setting the DTC

The DIC detects that the temperature is less than -40°C (-40°F) for more than 2 seconds.

Action Taken When the DTC Sets

OC is displayed by the DIC in the compass/temperature mode when the condition is present.

Conditions for Clearing the DTC

    • The DTC becomes history when the DIC no longer detects a failure.
    • The history DTC clears after 100 fault free ignition cycles.
    • The DIC receives the clear code command from the scan tool.

Test Description

The number below refer to the step number on the diagnostic table.

  1. Tests for the proper operation of the circuit in the low voltage range. If the fuse in the jumper opens when you perform this test, the signal circuit is shorted to voltage.

Step

Action

Yes

No

Schematic Reference: Driver Information System Schematics

1

Did you perform the Driver Information Center Diagnostic System Check?

Go to Step 2

Go to Diagnostic System Check - Driver Information Systems

2

Turn the ignition ON, with the engine OFF.

Does the DIC display OC?

Go to Step 3

Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems

3

  1. Turn the ignition OFF.
  2. Disconnect the ambient air temperature sensor.
  3. Connect a 3 amp fused jumper wire between the signal circuit of the ambient air temperature sensor and a good ground.
  4. Turn the ignition ON, with the engine OFF.

Does the DIC display SC?

Go to Step 5

Go to Step 4

4

Test the signal circuit of the ambient air temperature sensor for an open, for a high resistance, or for a short to voltage. Refer to Circuit Testing and to Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 10

Go to Step 7

5

Test the ground circuit of the ambient air temperature sensor for a high resistance or an open. Refer to Circuit Testing and to Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 10

Go to Step 6

6

Inspect for poor connections at the harness connector of the ambient air temperature sensor. Refer to Testing for Intermittent Conditions and Poor Connections and to Connector Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 10

Go to Step 8

7

Inspect for poor connections at the harness connector of the DIC. Refer to Testing for Intermittent Conditions and Poor Connections and to Connector Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 10

Go to Step 9

8

Replace the ambient air temperature sensor. Refer to Ambient Air Temperature Gage Sensor Replacement .

Did you complete the replacement?

Go to Step 10

--

9

Important: Calibrate the compass on the replacement DIC. Refer to Electronic Compass Calibration .

Replace the DIC. Refer to Driver Information Center Replacement .

Did you complete the replacement?

Go to Step 10

--

10

  1. Use the scan tool in order to clear the DTCs.
  2. Operate the vehicle within the Conditions for Running the DTC as specified in the supporting text.

Does the DTC reset?

Go to Step 2

System OK