For 1990-2009 cars

## DTC B0163, B0183, or B1405 C68

### Diagnostic Instructions

• | Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.

• | Review Strategy Based Diagnosis for an overview of the diagnostic approach.

• | Diagnostic Procedure Instructions provides an overview of each diagnostic category.

### DTC Descriptor

DTC B0163 02: Passenger Compartment Temperature Sensor Circuit Short to Ground
DTC B0163 05: Passenger Compartment Temperature Sensor Circuit Short to Battery or Open
DTC B0183 02: Solar Load Sensor Circuit Short to Ground
DTC B0183 05: Solar Load Sensor Circuit Short to Battery or Open
DTC B1405 02: Control Module Voltage Reference Output 2 Circuit Short to Ground
DTC B1405 05: Control Module Voltage Reference Output 2 Circuit Short to Battery or Open

### Diagnostic Fault Information

Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance
--- | --- | --- | --- | ---
Ambient Light/Sunload Sensor 12 V Reference | B1405 02 | B1405 05 | B1405 05 | --
Passenger Compartment Temperature Sensor Signal | B0163 02 | B0163 05 | B0163 05 | 1
Sunload Sensor Signal | B0183 02 | B0183 05 | B0183 05 | 1
Ambient Light/Sunload Sensor Ground | -- | B0163 05, B0183 05, B1405 05 | -- | --
1. Air Temperature Malfunction

### Circuit/System Description

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

This sensor assembly provides information about:

• | Sun heat intensity

• | Elevation

• | Azimuth

• | Passenger Compartment Temperature

The sunload sensor is connected to ground and to a 12 V clocked power supply through the HVAC control module. This clocked power supply is to power the sensor electronics and to work as a clock generator to the sunload sensor micro controller. The sensor uses a pulse signal for data identification and transferring the sun intensity measurement. At each positive transition from the clocked supply input, the sunload sensor micro controller will shift channels enabling new intensity measurement on the signal output to the HVAC control module. The signal voltage varies between 0-4 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

#### B0163 02 or B0163 05

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.

#### B0183 02

The 5 V identification pulse is not received.

#### B0183 05

The input signal is static and greater than 4.8 V.

#### B1405 02

Clocked supply for multi zone sensor is shorted to ground.

#### B1405 05

Clocked supply for multi zone sensor is shorted to voltage or open.

### Action Taken When the DTC Sets

• | The system will use the last valid values as default.

• | If no value is read at the time of fault, the HVAC Control Module uses 0 W/m² as intensity, 45° for elevation and -75° for azimuth.

### Conditions for Clearing the DTC

#### B0163 02 or B0163 05

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

#### B0183 02

The 5 V identification pulse will be received.

#### B0183 05

The correct pulse signal succession will be received.

#### B1405 02 or B1405 05

The condition for setting the DTC is no longer present.

### Reference Information

#### Schematic Reference

HVAC Schematics

#### Connector End View Reference

Component Connector End Views

#### Description and Operation

Automatic HVAC Description and Operation

#### Electrical Information Reference

• | Circuit Testing

• | Connector Repairs

• | Testing for Intermittent Conditions and Poor Connections

• | Wiring Repairs

#### Scan Tool Reference

Control Module References for scan tool information

### Circuit/System Verification

1. Verify that DTC B1405 02 or B1405 05 is not present.

⇒ | If DTC is present, refer to Ambient Light/Sunload Sensor Power Supply Malfunction.

2. Verify that DTC B0163 02 or B0163 05 is not present.

⇒ | If DTC is present, refer to Passenger Compartment Temperature Sensor Circuit Malfunction.

3. Verify that DTC B0183 02 or B0183 05 is not present.

⇒ | If DTC is present, refer to Sunload Sensor Circuit Malfunction.

4. Measure actual inside air temperature using a thermometer. Compare this value to the scan tool Passenger Compartment Air Temperature parameter. The measured temperature should be within 5°C (9°F) difference of parameter value.

⇒ | If not within the specified range, replace the B10B Ambient Light/Sunload Sensor.

### Circuit/System Testing

#### Ambient Light/Sunload Sensor Power Supply Malfunction

1. Ignition OFF, disconnect the harness connector at the B10B Ambient Light/Sunload Sensor and the X1 harness connector at the K33 HVAC Control Module.
2. Test for less than 5 Ω between the B10B Ambient Light/Sunload Sensor ground circuit terminal 6 and ground.

⇒ | If greater than the specified range, test the ground circuit for an open/high resistance.

3. Ignition ON, test for less than 0.3 V between the reference voltage circuit terminal 2 and ground.

⇒ | If greater than the specified range, test the reference voltage circuit for a short to voltage.

4. Ignition OFF, test for infinite resistance between the reference voltage circuit terminal 2 and ground.

⇒ | If less than the specified value, test the reference voltage circuit for a short to ground.

5. Test for less than 5 Ω between the B10B Ambient Light/Sunload Sensor reference voltage circuit terminal 2 and control circuit terminal 20 (X1) at the K33 HVAC Control Module harness connector

⇒ | If greater than the specified value, test the reference voltage circuit for an open/high resistance.

6. If all circuits test normal, replace the B10B Ambient Light/Sunload Sensor and verify the DTC does not reset.

⇒ | If the DTC resets, replace the K33 HVAC Control Module.

#### Passenger Compartment Temperature Sensor Circuit Malfunction

1. Ignition OFF, disconnect the harness connector at the B10B Ambient Light/Sunload Sensor.
2. Ignition ON, test for 4.8-5.2 V between the signal circuit terminal 3 and ground.

⇒ | If less than the specified range, test the signal circuit terminal for a short to ground or open/high resistance. If the circuit tests normal, replace the K33 HVAC Control Module.

⇒ | If greater than the specified range, test the signal circuit terminal for a short to battery. If the circuit tests normal, replace the K33 HVAC Control Module.

3. If all circuits test normal, replace the B10B Ambient Light/Sunload Sensor and verify the DTC does not reset.

⇒ | If the DTC resets, replace the K33 HVAC Control Module.

#### Sunload Sensor Circuit Malfunction

1. Ignition OFF, disconnect the harness connector at the B10B Ambient Light/Sunload Sensor.
2. Disconnect the harness connector X1 at the K33 HVAC Control Module.
3. Ignition ON, test for less than 0.3 V between the signal circuit terminal 4 and ground.

⇒ | If greater than the specified range, test the signal circuit for a short to voltage.

4. Ignition OFF, test for infinite resistance between the signal circuit terminal 4 and ground.

⇒ | If less than the specified value, test the signal circuit for a short to ground.

5. Test for less than 5 Ω between the B10B Ambient Light/Sunload Sensor signal circuit terminal 4 and control circuit terminal 13 (X1) at the K33 HVAC Control Module harness connector

⇒ | If greater than the specified value, test the signal circuit for an open/high resistance.

6. If all circuits test normal, replace the B10B Ambient Light/Sunload Sensor and verify the DTC does not reset.

⇒ | If the DTC resets, replace the K33 HVAC Control Module.

### Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

• | Sun Load Temperature and Headlamp Automatic Control Ambient Light Sensor Replacement

• | Control Module References for HVAC control module replacement, setup, and programming

## DTC B0163, B0183, or B1405 CJ2

### Diagnostic Instructions

• | Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.

• | Review Strategy Based Diagnosis for an overview of the diagnostic approach.

• | Diagnostic Procedure Instructions provides an overview of each diagnostic category.

### DTC Descriptor

DTC B0163 02: Passenger Compartment Temperature Sensor Circuit Short to Ground
DTC B0163 05: Passenger Compartment Temperature Sensor Circuit Short to Battery or Open
DTC B0183 02: Solar Load Sensor Circuit Short to Ground
DTC B0183 05: Solar Load Sensor Circuit Short to Battery or Open
DTC B1405 02: Control Module Voltage Reference Output 2 Circuit Short to Ground
DTC B1405 05: Control Module Voltage Reference Output 2 Circuit Short to Battery or Open

### Diagnostic Fault Information

Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance
--- | --- | --- | --- | ---
Ambient Light/Sunload Sensor 12 V Reference | B1405 02 | B1405 05 | B1405 05 | --
Passenger Compartment Temperature Sensor Signal | B0163 02 | B0163 05 | B0163 05 | 1
Sunload Sensor Signal | B0183 02 | B0183 05 | B0183 05 | 1
Ambient Light/Sunload Sensor Ground | -- | B0163 05, B0183 05, B1405 05 | -- | --
1. Air Temperature Malfunction

### Circuit/System Description

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

This sensor assembly provides information about:

• | Sun heat intensity

• | Elevation

• | Azimuth

• | Passenger Compartment Temperature

The sunload sensor is connected to ground and to a 12 V clocked power supply through the HVAC control module. This clocked power supply is to power the sensor electronics and to work as a clock generator to the sunload sensor micro controller. The sensor uses a pulse signal for data identification and transferring the sun intensity measurement. At each positive transition from the clocked supply input, the sunload sensor micro controller will shift channels enabling new intensity measurement on the signal output to the HVAC control module. The signal voltage varies between 0-4 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

#### B0163 02 or B0163 05

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.

#### B0183 02

The 5 V identification pulse is not received.

#### B0183 05

The input signal is static and greater than 4.8 V.

#### B1405 02

Clocked supply for multi zone sensor is shorted to ground.

#### B1405 05

Clocked supply for multi zone sensor is shorted to voltage or open.

### Action Taken When the DTC Sets

• | The system will use the last valid values as default.

• | If no value is read at the time of fault, the HVAC Control Module uses 0 W/m² as intensity, 45° for elevation and -75° for azimuth.

### Conditions for Clearing the DTC

#### B0163 02 or B0163 05

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

#### B0183 02

The 5 V identification pulse will be received.

#### B0183 05

The correct pulse signal succession will be received.

#### B1405 02 or B1405 05

The condition for setting the DTC is no longer present.

### Reference Information

#### Schematic Reference

HVAC Schematics

#### Connector End View Reference

Component Connector End Views

#### Description and Operation

Automatic HVAC Description and Operation

#### Electrical Information Reference

• | Circuit Testing

• | Connector Repairs

• | Testing for Intermittent Conditions and Poor Connections

• | Wiring Repairs

#### Scan Tool Reference

Control Module References for scan tool information

### Circuit/System Verification

1. Verify that DTC B1405 02 or B1405 05 is not present.

⇒ | If DTC is present, refer to Ambient Light/Sunload Sensor Power Supply Malfunction.

2. Verify that DTC B0163 02 or B0163 05 is not present.

⇒ | If DTC is present, refer to Passenger Compartment Temperature Sensor Circuit Malfunction.

3. Verify that DTC B0183 02 or B0183 05 is not present.

⇒ | If DTC is present, refer to Sunload Sensor Circuit Malfunction.

4. Measure actual inside air temperature using a thermometer. Compare this value to the scan tool Passenger Compartment Air Temperature parameter. The measured temperature should be within 5°C (9°F) difference of parameter value.

⇒ | If not within the specified range, replace the B10B Ambient Light/Sunload Sensor.

### Circuit/System Testing

#### Ambient Light/Sunload Sensor Power Supply Malfunction

1. Ignition OFF, disconnect the harness connector at the B10B Ambient Light/Sunload Sensor and the X1 harness connector at the K33 HVAC Control Module.
2. Test for less than 5 Ω between the B10B Ambient Light/Sunload Sensor ground circuit terminal 6 and ground.

⇒ | If greater than the specified range, test the ground circuit for an open/high resistance.

3. Ignition ON, test for less than 0.3 V between the reference voltage circuit terminal 2 and ground.

⇒ | If greater than the specified range, test the reference voltage circuit for a short to voltage.

4. Ignition OFF, test for infinite resistance between the reference voltage circuit terminal 2 and ground.

⇒ | If less than the specified value, test the reference voltage circuit for a short to ground.

5. Test for less than 5 Ω between the B10B Ambient Light/Sunload Sensor reference voltage circuit terminal 2 and control circuit terminal 20 (X1) at the K33 HVAC Control Module harness connector

⇒ | If greater than the specified value, test the reference voltage circuit for an open/high resistance.

6. If all circuits test normal, replace the B10B Ambient Light/Sunload Sensor and verify the DTC does not reset.

⇒ | If the DTC resets, replace the K33 HVAC Control Module.

#### Passenger Compartment Temperature Sensor Circuit Malfunction

1. Ignition OFF, disconnect the harness connector at the B10B Ambient Light/Sunload Sensor.
2. Ignition ON, test for 4.8-5.2 V between the signal circuit terminal 3 and ground.

⇒ | If less than the specified range, test the signal circuit terminal for a short to ground or open/high resistance. If the circuit tests normal, replace the K33 HVAC Control Module.

⇒ | If greater than the specified range, test the signal circuit terminal for a short to battery. If the circuit tests normal, replace the K33 HVAC Control Module.

3. If all circuits test normal, replace the B10B Ambient Light/Sunload Sensor and verify the DTC does not reset.

⇒ | If the DTC resets, replace the K33 HVAC Control Module.

#### Sunload Sensor Circuit Malfunction

1. Ignition OFF, disconnect the harness connector at the B10B Ambient Light/Sunload Sensor.
2. Disconnect the harness connector X1 at the K33 HVAC Control Module.
3. Ignition ON, test for less than 0.3 V between the signal circuit terminal 4 and ground.

⇒ | If greater than the specified range, test the signal circuit for a short to voltage.

4. Ignition OFF, test for infinite resistance between the signal circuit terminal 4 and ground.

⇒ | If less than the specified value, test the signal circuit for a short to ground.

5. Test for less than 5 Ω between the B10B Ambient Light/Sunload Sensor signal circuit terminal 4 and control circuit terminal 13 (X1) at the K33 HVAC Control Module harness connector

⇒ | If greater than the specified value, test the signal circuit for an open/high resistance.

6. If all circuits test normal, replace the B10B Ambient Light/Sunload Sensor and verify the DTC does not reset.

⇒ | If the DTC resets, replace the K33 HVAC Control Module.

### Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

• | Sun Load Temperature and Headlamp Automatic Control Ambient Light Sensor Replacement

• | Control Module References for HVAC control module replacement, setup, and programming