Operation CHARM: Car repair manuals for everyone.

B0163




DTC B0163

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 Instructionsprovides an overview of each diagnostic category.

DTC Descriptors
DTC B0163 02
- Passenger Compartment Temperature Sensor Circuit Short to Ground

DTC B0163 05
- Passenger Compartment Temperature Sensor Circuit High Voltage/Open

Diagnostic Fault Information






Circuit/System Description

The ambient light/sunload sensor includes the sunload sensor and passenger compartment temperature sensor.

This sensor assembly provides information about:

* Sun heat intensity
* Passenger compartment temperature

The vehicle uses a sunload sensor that is integrated into one sensor assembly along with the passenger compartment temperature sensor. Low reference and signal circuits enable the sensor to operate. The sensor signal varies between 0-5 V.

The passenger compartment temperature sensor is a negative temperature co-efficient thermistor. A signal and low reference circuit enables the sensor to operate. As the air temperature increases, the sensor resistance decreases. The sensor signal varies between 0-5 V.

Bright or high intensity light causes the vehicles interior temperature to increase. The HVAC system compensates for the increased temperature by diverting additional cool air into the vehicle.

Conditions for Running the DTC

* Ignition ON
* The HVAC control module is ON.

Conditions for Setting the DTC

The HVAC control module detects the sensor signal out of range. The signal voltage is less than 0.1 V or greater than 4.9 V for more than 50 ms.

Action Taken When the DTC Sets

The system operates using a default value.

Conditions for Clearing the DTC

The sensor signal is within specified range between 0.1-4.9 V.

Reference Information
Schematic Reference

HVAC Schematics HVAC - Automatic
Connector End View Reference

Component Connector End Views Sunshade - Left (D6I)
Description and Operation

Automatic HVAC Description and Operation HVAC - Automatic
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

Circuit/System Testing

1. Ignition OFF, disconnect the harness connector at the B10B ambient light/ sunload sensor. It may take up to 2 minutes for all vehicle systems to power down.
2. Test for less than 10 ohm between the low reference circuit terminal 6 and ground.

If 10 ohm or greater

1. Ignition OFF, disconnect the harness connector at the K33 HVAC control module.
2. Test for less than 2 ohm in the low reference circuit end to end.

If 2 ohm or greater, repair the open/high resistance in the circuit.
If less than 2 ohm, replace the K33 HVAC control module.

If less than 10 ohm

3. Ignition ON.
4. Verify the scan tool parameter Passenger Compartment Air Temperature (Unfiltered) is less than -35°F.

If -35°F or greater

1. Ignition OFF, disconnect the harness connector at the K33 HVAC control module.
2. Test for infinite resistance between the signal circuit terminal 3 and ground.

If less than infinite resistance, repair the short to ground on the circuit.
If infinite resistance, replace the K33 HVAC control module.

If less than -35°F

5. Install a 3 A fused jumper wire between the signal circuit terminal 3 and the low reference circuit terminal 6.
6. Verify the scan tool parameter Passenger Compartment Air Temperature (Unfiltered) is greater than 240°F.

If 240°F or less

1. Ignition OFF, disconnect the harness connector at the K33 HVAC control module, 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 ohm in the signal circuit end to end.

If 2 ohm or greater, repair the open/high resistance in the circuit.
If less than 2 ohm, replace the K33 HVAC control module.

If greater than 240°F

7. Test or replace the B10B ambient light sensor.

Repair Instructions

Perform the Diagnostic Repair Verification Verification Tests after completing the diagnostic procedure.

* HVAC Component Replacement Reference HVAC Component Replacement Reference
* Control Module References Control Module Referencesfor HVAC control module replacement, programming and setup