Outside Air Temperature Display Malfunction
Outside Air Temperature Display Malfunction
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.
Diagnostic Fault Information
Circuit/System Description
The instrument cluster monitors the ambient air temperature sensor with a low reference circuit and 5 V signal circuit. The instrument cluster monitors the voltage drop across the sensor, which is proportional to temperature. When the ambient air temperatures are cold, the resistance of the sensor is high and the voltage signals are high. When the ambient air temperatures are hot, the resistance of the sensors is low and the voltage signals are low. The instrument cluster converts the voltage value to a temperature value of Celsius or Fahrenheit that will be displayed by the display.
Reference Information
Schematic Reference
Instrument Cluster Schematics Instrument Cluster Schematics
Connector End View Reference
Component Connector End Views Outside Rearview Mirror - Driver
Description and Operation
Driver Information Center (DIC) Description and Operation Driver Information Center (DIC)
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 Control Module References for scan tool information
Circuit/System Verification
1. Ignition ON.
2. Verify the scan tool Ambient Air Temperature parameter between -40°C (-40°F) to +88°C (+190°F) and changes with air temperature changes.
• If parameter is not between -40°C (-40°F) to +88°C (+190°F) or changes with air temperature changes
Refer to Circuit/System Testing.
• If parameter is between -40°C (-40°F) to +88°C (+190°F) and changes with air temperature changes
3. All OK.
Circuit/System Testing
1. Ignition OFF and all vehicle systems OFF, disconnect the harness connector at the B9 ambient air temperature sensor. It may take up to 2 minutes for all vehicle systems to power down.
2. Test for less than 1 V between the low reference circuit terminal 2 and ground.
• If 1 V or greater
repair the short to voltage on the circuit.
• If less than 1 V
3. Test for less than 10 ohms between the low reference circuit terminal 2 and ground.
• If 10 ohms or greater
1. Ignition OFF, disconnect the harness connector at the P16 instrument cluster.
2. Test for less than 2 ohms in the low reference circuit end to end.
• If 2 ohms or greater, repair the open/high resistance in the circuit.
• If less than 2 ohms, replace the P16 instrument cluster.
• If less than 10 ohms
4. Ignition ON.
5. Verify the scan tool Ambient Air Temperature parameter is greater than 98%.
• If 98% or less
1. Ignition OFF, disconnect the harness connector at the P16 instrument cluster.
2. Test for infinite resistance between the signal circuit and ground.
• If less than infinite resistance, repair the short to ground on the circuit.
• If infinite resistance, replace the P16 instrument cluster.
• If greater than 98%
6. Install a 3 A fused jumper wire between the signal circuit terminal 1 and the low reference circuit terminal B.
7. Verify the scan tool Ambient Air Temperature parameter is less than 8%.
• If 8% or greater
1. Ignition OFF, disconnect the harness connector at the P16 instrument cluster, ignition ON.
2. Test for less than 1 V between the signal circuit and ground.
• If 1 V or greater, repair the short to voltage on the circuit.
• If less than 1 V
3. Ignition OFF
4. Test for less than 2 ohms in the signal circuit end to end.
• If 2 ohms or greater, repair the open/high resistance in the circuit.
• If less than 2 ohms, replace the P16 instrument cluster.
• If less than 8%
8. Test or replace the B9 Ambient Air Temperature Sensor.
Component Testing
Static Test
1. Test the B9 Air Temperature Sensor - Ambient by varying the sensor temperature while monitoring the sensor resistance.
2. Compare the readings with the Ambient Air Temperature Sensor Resistance [1][2]Ambient Temperature Sensor / Switch HVAC.
• If not within the specified range, replace the B9 Air Temperature Sensor - Ambient.
Repair Instructions
Perform the Diagnostic Repair Verification Verification Tests after completing the repair.
* Ambient Air Temperature Gauge Sensor Replacement Ambient Air Temperature Gauge Sensor Replacement
* Control Module References Control Module References for module replacement, setup, and programming