Displays and Gauges
DTC B0158
Diagnostic Instructions
* Perform the Diagnostic System Check - Vehicle (Diagnostic System Check - Vehicle) prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis (Strategy Based Diagnosis) for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions (Diagnostic Procedure Instructions) provides an overview of each diagnostic category.
DTC Descriptors
DTC B0158 02
- Outside Air Temperature (OAT) Sensor Short to Ground
DTC B0158 05
- Outside Air Temperature (OAT) Sensor Short to Battery or Open
Diagnostic Fault Information
Circuit/System Description
The ambient air temperature sensor is a variable resistor interfaced to the body control module (BCM). The BCM monitors the ambient air temperature sensor. The ambient air temperature sensor is a 2-wire negative temperature coefficient thermistor. The BCM applies 5 volts to an internal input resistor connected to the signal circuit of the ambient air temperature sensor. The BCM provides the ambient air temperature sensor with a low reference circuit. When the ambient air temperature is cold, the sensor resistance is high and the signal voltage is high. When the ambient air temperature is hot, the sensor resistance is low and the signal voltage is low. The BCM provides the logic for reading the sensor, filtering the data and transmitting the information via the serial data circuit to the driver information center (DIC) for display. The temperature is sent to the IPC in degrees Celsius. The IPC is responsible for displaying the temperature and converting to degrees Fahrenheit if necessary. Two serial data signals are ultimately generated. An unfiltered value and a filtered value for use by the DIC display. The BCM also provides the sensor out-of-range detection and compensates for engine temperature by utilizing vehicle speed and engine off time duration.
Conditions for Running the DTC
* The ignition is in ACC or RUN.
* The system voltage is between 9-16 volts
Conditions for Setting the DTC
The BCM detects that the ambient air temperature sensor voltage is less than 0.4 volt or more than 4.8 volts.
Action Taken When the DTC Sets
* The default value of 3°C (38°F) will be substituted for the ambient air temperature sensor data by the BCM.
* The driver information center (DIC) will display SET TEMPERATURE when ON.
Conditions for Clearing the DTC
* The DTC becomes history when the BCM no longer detects a fault.
* The history DTC clears after 40 malfunction-free ignition cycles.
Reference Information
Schematic Reference
Instrument Cluster Schematics (Instrument Cluster Schematics)
Connector End View Reference
Component Connector End Views (Connector Views)
Description and Operation
* Driver Information Center (DIC) Description and Operation (Driver Information Center (DIC))
* Instrument Cluster Description and Operation (Instrument Cluster)
Electrical Information Reference
* Circuit Testing (Circuit Testing)
* Connector Repairs (Connector Repairs)
* Testing for Intermittent Conditions and Poor Connections (Testing for Intermittent Conditions and Poor Connections)
* Wiring Repairs (Wiring Repairs)
Scan Tool Reference
Control Module References (Programming and Relearning) for scan tool information
Circuit/System Testing
1. Ignition OFF, disconnect the harness connector at the ambient air temperature sensor.
2. Ignition OFF, test for less than 1 ohm between the low reference circuit terminal B and ground.
• If greater than the specified range, test the low reference circuit for an open/high resistance. If the circuit tests normal, replace the BCM.
3. Ignition ON, verify the scan tool Ambient Air Temp. Sensor parameter is greater than 4.7 volts.
• If less than the specified range, test the signal circuit terminal A for a short to ground. If the circuit tests normal, replace the BCM.
4. Install a 3-amp fused jumper wire between the signal circuit terminal A and the low reference circuit terminal B. Verify the scan tool Ambient Air Temp. Sensor parameter is less than 0.4 volt.
• If greater than the specified range, test the signal circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the BCM.
5. If all circuits test normal, test or replace the ambient air temperature sensor.
Repair Instructions
Perform the Diagnostic Repair Verification (Verification Tests) after completing the diagnostic procedure.
* Ambient Air Temperature Gauge Sensor Replacement (Service and Repair)
* Control Module References (Programming and Relearning) for the BCM replacement, setup, and programming