Outside Air Temperature Display Inaccurate or Inoperative
Outside Air Temperature Display Inaccurate or Inoperative
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 (Connector End Views By Name)
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 (Programming and Relearning)for scan tool information
Circuit/System Verification
Ignition ON, observe the scan tool Ambient Air Temperature parameter. The reading should be between -40°C (-40°F) to +88°C (+190°F) and change with air temperature changes.
Circuit/System Testing
1. Ignition OFF, disconnect the harness connector at the B9 Air Temperature Sensor - Ambient.
2. Ignition ON, test for 4.8-5.2 V between the signal circuit terminal 1 and ground.
• If greater than the specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the P16 Instrument Cluster.
• If less than the specified range, test the signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the P16 Instrument Cluster.
3. Install a 3 A fused jumper wire between the signal circuit terminal 1 and the low reference circuit terminal 2. Verify the scan tool Ambient Air Temperature parameter displays greater than 54°C (130°F).
• If less than the specified range, test the low reference circuit a short to voltage or an open/high resistance. If the circuit tests normal, replace the P16 Instrument Cluster.
4. Verify the accuracy of the B9 Air Temperature Sensor - Ambient. Refer to 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.
5. If all circuits test normal, test the P16 Instrument Cluster.
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 instrument cluster or display replacement, setup, and programming