Circuit Description
The instrument panel cluster (IPC) monitors the signal circuit of the ambient air temperature sensor. The ambient air temperature is a thermistor which varies in resistance as the temperature changes. As the resistance of the ambient air temperature sensor increases, the IPC senses a larger voltage drop across the sensor, indicating a lower temperature. As the resistance of the ambient air temperature sensor decreases, the IPC senses a smaller voltage drop across the sensor, indicating a higher temperature. The ambient air temperature is displayed in the DIC by the IPC. The ambient air temperature sensor is interfaced with the IPC via two discreet inputs.
DTC Descriptor
This diagnostic procedure supports the following DTC:
| • | DTC B0160 Outside Air Temperature Sensor Circuit Low |
| • | DTC B0161 Outside Air Temperature Sensor Circuit High |
Conditions for Running the DTC
The IPC must be fully operational within a continuous voltage supply of 9-16 volts.
Conditions for Setting the DTC
DTC B0160 sets when the instrument panel cluster (IPC) detects that the temperature is greater than 190°F (88°C) for more than 2 seconds.
DTC B0161 sets when the IPC detects that the temperature is less than -40°F (-40°C) for more than 2 seconds.
Action Taken When the DTC Sets
| • | "SC" is displayed in the DIC by the IPC when the ambient air temperature sensor resistance value is less than the lowest ambient air temperature sensor resistance threshold and DTC B0160 is present. |
| • | "OC" is displayed in the DIC by the IPC when the ambient air temperature sensor resistance value is greater than the highest ambient air temperature sensor resistance threshold and DTC B0161 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 IPC receives the clear code command from the scan tool. |
Step | Action | Yes | No |
|---|---|---|---|
Schematic Reference: Instrument Cluster Schematics or Driver Information System Schematics | |||
1 | Did you perform the Diagnostic System Check - Vehicle? | Go to Step 2 | Go to Diagnostic System Check - Vehicle in Vehicle DTC Information |
2 | Turn the ignition ON, with the engine OFF. Does the driver information center (DIC) display SC or OC? | Go to Step 3 | Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems |
3 |
Does the DIC display OC? | Go to Step 4 | Go to Step 7 |
4 |
Does the DIC display SC? | Go to Step 6 | Go to Step 5 |
5 | Test the signal circuit of the ambient air temperature sensor for an open, for a short to voltage or for a high resistance. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | Go to Step 12 | Go to Step 8 |
6 | Test the ground circuit of the ambient air temperature sensor for an open or for a high resistance. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | Go to Step 12 | Go to Step 9 |
7 | Test the signal circuit of the ambient air temperature sensor for a short to ground. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | Go to Step 12 | Go to Step 8 |
8 | Inspect for poor connections at the harness connector of the instrument panel cluster (IPC). Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems. Did you find and correct the condition? | Go to Step 12 | Go to Step 10 |
9 | 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 12 | Go to Step 11 |
10 | Replace the IPC. Refer to Control Module References in Computer/Integrating Systems for replacement, setup, and programming. Did you complete the replacement? | Go to Step 12 | -- |
11 | Replace the ambient air temperature sensor. Refer to Ambient Air Temperature Gage Sensor Replacement . Did you complete the replacement? | Go to Step 12 | -- |
12 |
Does the DTC reset? | Go to Step 2 | System OK |
