HVAC System - Automatic: Diagnosis Cadillac SRX II facelift

Diagnostic Code Index

DIAGNOSTIC CODE INDEX

Diagnostic Instructions

1. Perform the «Diagnostic System Check - Vehicle»(ref-644698-S03753758692014072300000) prior to using this diagnostic procedure.
2. Review «Strategy Based Diagnosis»(ref-644698-S14897089332014072300000) for an overview of the diagnostic approach.
3. «Diagnostic Procedure Instructions»(ref-644698-S14982480842014072300000) provides an overview of each diagnostic category.

DTC Descriptors

For symptom byte information, refer to Symptom Byte List .

Diagnostic Fault Information

Conditions for Running the DTC

1. Ignition ON
2. The HVAC control module is ON.

Conditions for Setting the DTC

B0163 02

The input signal is out of range. The HVAC control module detects voltage less than 0.1 V on the temperature signal circuit.

B0163 05

The input signal is out of range. The HVAC control module detects voltage greater than 4.9 V on the temperature signal circuit.

B0183 02

The input signal is out of range. The HVAC control module detects voltage less than 0.1 V on the solar sensor signal circuit.

B0183 05

The input signal is out of range. The HVAC control module detects voltage greater than 4.9 V on the solar sensor signal circuit.

B1405 02

The input signal is out of range. The HVAC control module detects voltage less than 10 V on the clock/power supply circuit.

B1405 05

The input signal is out of range. The HVAC control module detects a short to voltage or an open the clock/power supply circuit.

Action Taken When the DTC Sets

B0163 02, B0163 05, B0183 02, B0183 05

The system will use the last valid values as a default.

B1405 02, B1405 05

If no value is read at the time of fault, the HVAC control module uses 0 W/m 2 as intensity.

Conditions for Clearing the DTC

The condition for setting the DTC is no longer present.

Circuit/System Testing

Low Reference Test

1. Ignition OFF and all vehicle systems OFF, disconnect the harness connector at the B10B Ambient Light/Sunload Sensor. It may take up to 10 min for all vehicle systems to power down.
2. Test for less than 10 ohms between the low reference circuit terminal 6 and ground. If 10 ohms or greater Ignition OFF, disconnect the harness connector at the K33 HVAC Control Module. 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 K33 HVAC Control Module. If less than 10 ohms
3. Test or replace the B10B Ambient Light/Sunload Sensor.

DTC B0163

1. Ignition OFF, disconnect the harness connector at the B10B Ambient Light/Sunload Sensor, ignition ON.
2. Verify the scan tool Passenger Compartment Air Temperature (Unfiltered) parameter is less than -37°C (-35°F). If -37°C (-35°F) or greater Ignition OFF, disconnect the harness connector at the K33 HVAC Control Module. 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 -37°C (-35°F)
3. Install a 3 A fused jumper wire between the signal circuit terminal 3 and the low reference circuit terminal 6.
4. Verify the scan tool parameter Passenger Compartment Air Temperature (Unfiltered) parameter is greater than 78°C (172°F). If 78°C (172°F) or less Ignition OFF, remove the jumper wire and disconnect the harness connector at the K33 HVAC Control Module, ignition ON. 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 Ignition OFF. 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 K33 HVAC Control Module. If greater than 78°C (172°F)
5. Test or replace the B10B Ambient Light/Sunload Sensor.

DTC B0183

1. Ignition OFF, disconnect the harness connector at the B10B Ambient Light/Sunload Sensor, ignition ON.
2. Test for 4.8-5.2 V between the signal circuit terminal 4 and ground. If less than 4.8 V Ignition OFF, disconnect the harness connector at the K33 HVAC Control Module. 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 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 K33 HVAC Control Module. If greater than for 5.2 V Ignition OFF, disconnect the harness connector at the K33 HVAC Control Module, ignition ON. 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, replace the K33 HVAC Control Module. If between 4.8-5.2 V
3. Test or replace the B10B Ambient Light/Sunload Sensor.
4. Verify DTC B0183 did not reset. If DTC B0183 reset Replace the K33 HVAC Control Module. If DTC B0183 did not reset
5. All OK.

DTC B1405

1. Ignition OFF, disconnect the harness connector at the B10B Ambient Light/Sunload Sensor, ignition ON.
2. Test for greater than 10 V between signal circuit terminal 2 and ground. If less than 10 V Ignition OFF, disconnect the harness connector at the K33 HVAC Control Module. Test for infinite resistance between signal circuit terminal 2 and ground. If less than infinite resistance, repair the short to ground on the circuit. If infinite resistance 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 K33 HVAC Control Module. If 10 V or greater
3. Ignition OFF, disconnect the harness connector at the K33 HVAC Control Module, ignition ON.
4. Test for less than 1 V between the signal circuit terminal 2 and ground. If 1 V or greater Repair the short to voltage on the circuit. If less than 1 V
5. Test or replace the B10B Ambient Light/Sunload Sensor.
6. Verify DTC B1405 did not reset. If DTC B1405 reset Replace the K33 HVAC Control Module. If DTC B1405 did not reset
7. All OK.

1. Perform the «Diagnostic System Check - Vehicle»(ref-644698-S03753758692014072300000) prior to using this diagnostic procedure.
2. Review «Strategy Based Diagnosis»(ref-644698-S14897089332014072300000) for an overview of the diagnostic approach.
3. «Diagnostic Procedure Instructions»(ref-644698-S14982480842014072300000) provides an overview of each diagnostic category.

1. Ignition ON.
2. The HVAC control module is ON.

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.

The system operates using a default value.

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

With Scan Tool Support

1. Ignition OFF and all vehicle systems OFF, disconnect the harness connector at the appropriate temperature sensor. It may take up to 10 min for all vehicle systems to power down.
2. Test for less than 10 ohms between the low reference circuit terminal B and ground. If 10 ohms or greater Ignition OFF, disconnect the harness connector at the K33 HVAC Control Module. 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 K33 HVAC Control Module. If less than 10 ohms
3. Ignition ON.
4. Verify the appropriate scan tool temperature sensor parameter is less than -37°C (-35°F) If greater than -37°C (-35°F) Ignition OFF, disconnect the harness connector at the K33 HVAC Control Module. Test for infinite resistance between the signal circuit terminal A 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 -37°C (-35°F) or less
5. Install a 3 A fused jumper wire between the signal circuit terminal A and the low reference circuit terminal B.
6. Verify the scan tool temperature sensor parameter is greater than 110°C (230°F). If less than 110°C (230°F) Ignition OFF, remove the jumper wire and disconnect the harness connector at the K33 HVAC Control Module, ignition ON. 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 Ignition OFF 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 K33 HVAC Control Module. If 110°C (230°F) or greater
7. Test or replace the temperature sensor.

Without Scan Tool Support

1. Ignition OFF and all vehicle systems OFF, disconnect the harness connector at the appropriate temperature sensor. It may take up to 10 min for all vehicle systems to power down.
2. Test for less than 10 ohms between the low reference circuit terminal B and ground. If 10 ohms or greater Ignition OFF, disconnect the harness connector at the K33 HVAC Control Module. 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 K33 HVAC Control Module. If less than 10 ohms
3. Test for 4.8-5.2 V between the signal circuit terminal A and ground. If less than 4.8 V Ignition OFF, disconnect the harness connector at the K33 HVAC Control Module. 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 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 K33 HVAC Control Module. If greater than 5.2 V Ignition OFF, disconnect the harness connector at the K33 HVAC Control Module, ignition ON. 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, replace the K33 HVAC Control Module. If between 4.8-5.2 V
4. Test or replace the temperature sensor.
5. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.
6. Verify the DTC does not set. If the DTC sets Replace the K33 HVAC Control Module. If the DTC does not set
7. All OK

1. Perform the «Diagnostic System Check - Vehicle»(ref-644698-S03753758692014072300000) prior to using this diagnostic procedure.
2. Review «Strategy Based Diagnosis»(ref-644698-S14897089332014072300000) for an overview of the diagnostic approach.
3. «Diagnostic Procedure Instructions»(ref-644698-S14982480842014072300000) provides an overview of each diagnostic category.

For symptom byte information, refer to Symptom Byte List .

1. Ignition ON.
2. The HVAC control module is ON.

B018A 02, B048C 02, or B048F 02

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

B018A 05, B048C 05, B048F 05 or B1395 07

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

B1395 03

The HVAC control module detects the 5 V reference voltage out of range. The 5 V reference voltage is less than 4.5 V for more than 50 ms.

B1395 07

The HVAC control module detects the 5 V reference voltage out of range. The 5 V reference voltage is greater than 5.5 V for more than 50 ms.

1. The system will use the last valid values as default.
2. If no value is read at the time of fault, the HVAC control module uses 60% for humidity.

The condition for setting the DTC is no longer present.

1. Ignition OFF and all vehicle systems OFF, disconnect the harness connector at the B160 Windshield Temperature and Inside Moisture Sensor. It may take up to 10 min for all vehicle systems to power down.
2. Test for less than 10 ohms between the low reference circuit terminal 3 and ground. If 10 ohms or greater Ignition OFF, disconnect the harness connectors at the K33 HVAC Control Module. 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 K33 HVAC Control Module. If less than 10 ohms
3. Ignition ON.
4. Test for 4.8-5.2 V between the 5 V reference circuit terminal 1 and ground. If less than 4.8 V Ignition OFF, disconnect the harness connectors at the K33 HVAC Control Module. Test for infinite resistance between the 5 V reference circuit and ground. If less than infinite resistance, repair the short to ground on the circuit. If infinite resistance Test for less than 2 ohms in the 5 V 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 K33 HVAC Control Module. If greater than 5.2 V Ignition OFF, disconnect the harness connectors at the K33 HVAC Control Module, ignition ON. Test for less than 1 V between the 5 V reference circuit and ground. If 1 V or greater, repair the short to voltage on the circuit. If less than 1 V, replace the K33 HVAC Control Module. If between 4.8-5.2 V
5. Verify the scan tool parameters listed below are less than -37°C (-35°F). Windshield Temperature Passenger Compartment Humidity Sensor Temperature If -37°C (-35°F) or greater Ignition OFF, disconnect the harness connectors at the K33 HVAC Control Module. Test for infinite resistance between the signal circuit terminals listed below and ground: Windshield temperature sensor signal terminal 4 Passenger compartment humidity sensor temperature signal terminal 5 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 -37°C (-35°F)
6. Install a 3 A fused jumper wire between the low reference circuit terminal 3 and each signal circuit terminal listed below: Windshield temperature sensor signal terminal 4 Passenger compartment humidity sensor temperature signal terminal 5
7. Verify the appropriate scan tool parameter listed below is greater than 114°C (238°F). Windshield Temperature Passenger Compartment Humidity Sensor Temperature If 114°C (238°F) or less Ignition OFF, remove the jumper wire and disconnect the harness connectors at the K33 HVAC Control Module, ignition ON. Test for less than 1 V between the signal circuit terminals listed below and ground: Windshield temperature sensor signal terminal 4 Passenger compartment humidity sensor temperature signal terminal 5 If 1 V or greater, repair the short to voltage on the circuit. If less than 1 V 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 K33 HVAC Control Module. If greater than 114°C (238°F)
8. Remove the jumper wire.
9. Verify the scan tool Passenger Compartment Humidity parameter is greater than 95%. If 95% or less Ignition OFF, disconnect the harness connectors at the K33 HVAC Control Module, ignition ON. Test for infinite resistance between the signal circuit terminal 2 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 greater than 95%
10. Install a 3 A fused jumper wire between the passenger compartment humidity signal circuit terminal 2 and the low reference circuit terminal 3.
11. Verify the scan tool Passenger Compartment Humidity Sensor parameter is less than 5%. If 5% or greater Ignition OFF, remove the jumper wire and disconnect the harness connectors at the K33 HVAC Control Module, ignition ON. Test for less than 1 V between the signal circuit terminal 2 and ground. If 1 V or greater, repair the short to voltage on the circuit. If less than 1 V 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 K33 HVAC Control Module. If less than 5%
12. Test or replace the B160 Windshield Temperature and Inside Moisture Sensor.

1. Perform the «Diagnostic System Check - Vehicle»(ref-644698-S03753758692014072300000) prior to using this diagnostic procedure.
2. Review «Strategy Based Diagnosis»(ref-644698-S14897089332014072300000) for an overview of the diagnostic approach.
3. «Diagnostic Procedure Instructions»(ref-644698-S14982480842014072300000) provides an overview of each diagnostic category.

1. Ignition ON.
2. The HVAC control module is ON.

B0193 01

The voltage at the HVAC control module output to the blower motor control module is always high.

B0193 06

The voltage at the HVAC control module output to the blower motor control module is always low or fluctuating.

The blower motor is inoperative.

The condition for setting the DTC is no longer present.

Diagnostic Aids

Inspect the motor shaft for rust or other foreign material which may prohibit proper motor operation.

If the motor operates properly please reinstall it and check for Preliminary Information or Technical Service Bulletins.

1. Ignition OFF and all vehicle systems OFF, disconnect the X1 harness connector at the K8 Blower Motor Control Module. It may take up to 2 min for all vehicle systems to power down.
2. Test for less than 10 ohms between the ground circuit terminal 5 and ground. If 10 ohms or greater Ignition OFF. Test for less than 2 ohms in the ground circuit end to end. If 2 ohms or greater, repair the open/high resistance in the circuit. If less than 2 ohms, repair the open/high resistance in the ground connection. If less than 10 ohms
3. Ignition ON.
4. Verify a test lamp illuminates between the B+ circuit terminal 6 and ground. If the test lamp does not illuminate and the circuit fuse is good Ignition OFF, remove the test lamp. Test for less than 2 ohms in the B+ circuit end to end. If 2 ohms or greater, repair the open/high resistance in the circuit. If less than 2 ohms, verify the fuse is not open and there is voltage at the fuse. If the test lamp does not illuminate and the circuit fuse is open Ignition OFF, remove the test lamp. Test for infinite resistance between the B+ circuit terminal 6 and ground. If less than infinite resistance, repair the short to ground on the circuit. If infinite resistance Disconnect the X2 harness connector at the K8 Blower Motor Control Module and disconnect the harness connector at the M8 Blower Motor. Test for infinite resistance between the M8 Blower Motor B+ circuit terminal B and ground. If less than infinite resistance, repair the short to ground on the circuit. If infinite resistance, test or replace the M8 Blower Motor. If the test lamp illuminates
5. Remove the test lamp.
6. Verify the resistance between the control circuit terminal 3 and ground varies from 100K ohms to 150K ohms while changing blower speeds. If the resistance does not change from 100K ohms to 150K ohms Ignition OFF, disconnect the X2 harness connector at the K33 HVAC Control Module, ignition ON. Test for less than 1 V between the control circuit and ground. If 1 V or greater, repair the short to voltage on the circuit. If less than 1 V Test for infinite resistance between the control circuit and ground. If less than infinite resistance, repair the short to ground on the circuit. If infinite resistance. Test for less than 2 ohms in the control circuit end to end. If 2 ohms or greater, repair the open/high resistance in the circuit. If less than 2 ohms replace the K33 HVAC Control Module. If the resistance does change from 100K ohms to 150K ohms
7. Ignition OFF, connect the X1 harness connector at the K8 Blower Motor Control Module and disconnect the harness connector at the M8 Blower Motor, ignition ON and blower ON.
8. Verify a test lamp illuminates between the B+ terminal B and ground. If the test lamp does not illuminate Ignition OFF, disconnect the X2 harness connector at the K8 Blower Motor Control Module. Test for less than 2 ohms in the B+ circuit end to end. If 2 ohms or greater, repair the open/high resistance in the circuit. If less than 2 ohms replace the K8 Blower Motor Control Module. If the test lamp illuminates
9. Connect a test lamp between the B+ circuit terminal B and control circuit terminal A, ignition ON.
10. Verify the test lamp becomes progressively brighter as the blower speed is increased and progressively dimmer as the blower speed is decreased. If the test lamp does not illuminate Ignition OFF, remove the test lamp and disconnect the X2 harness connector at the K8 Blower Motor Control Module, ignition ON. Test for less than 1 V between the control circuit terminal 2 and ground. If 1 V or greater, repair the short to voltage on the circuit. If less than 1 V Test for less than 2 ohms in the control circuit end to end. If 2 ohms or greater, repair the open/high resistance in the circuit. If less than 2 ohms replace the K8 Blower Motor Control Module. If the test lamp illuminates, but does not change in brightness Ignition OFF, remove the test lamp and disconnect the X2 harness connector at the K8 Blower Motor Control Module. Test for infinite resistance between the control circuit terminal 2 and ground. If less than infinite resistance, repair the short to ground on the circuit. If infinite resistance, replace the K8 Blower Motor Control Module. If the test lamp changes in brightness as the blower speed is changed
11. Test or replace the M8 Blower Motor.

1. Perform the «Diagnostic System Check - Vehicle»(ref-644698-S03753758692014072300000) prior to using this diagnostic procedure.
2. Review «Strategy Based Diagnosis»(ref-644698-S14897089332014072300000) for an overview of the diagnostic approach.
3. «Diagnostic Procedure Instructions»(ref-644698-S14982480842014072300000) provides an overview of each diagnostic category.

1. Ignition ON.
2. The HVAC control module is ON.

B0208 01

The voltage at the HVAC control module output to the auxiliary blower motor control module is always high.

B0208 06

The voltage at the HVAC control module output to the auxiliary blower motor control module is always low or fluctuating.

The auxiliary blower motor is inoperative.

The condition for setting the DTC is no longer present.

Inspect the motor shaft for rust or other foreign material which may prohibit proper motor operation.

If the motor operates properly please reinstall it and check for Preliminary Information or Technical Service Bulletins.

1. Ignition OFF and all vehicle systems OFF, disconnect the X1 harness connector at the K8A Blower Motor Control Module - Auxiliary. It may take up to 2 min for all vehicle systems to power down.
2. Test for less than 10 ohms between the ground circuit terminal 4 and ground. If 10 ohms or greater Ignition OFF. Test for less than 2 ohms in the ground circuit end to end. If 2 ohms or greater, repair the open/high resistance in the circuit. If less than 2 ohms, repair the open/high resistance in the ground connection. If less than 10 ohms
3. Ignition ON.
4. Verify a test lamp illuminates between the B+ circuit terminal 2 and ground. If the test lamp does not illuminate and the circuit fuse is good Ignition OFF, remove the test lamp. Test for less than 2 ohms in the B+ circuit end to end. If 2 ohms or greater, repair the open/high resistance in the circuit. If less than 2 ohms, verify the fuse is not open and there is voltage at the fuse. If the test lamp does not illuminate and the circuit fuse is open Ignition OFF, remove the test lamp. Test for infinite resistance between the B+ circuit and ground. If less than infinite resistance, repair the short to ground on the circuit. If infinite resistance Disconnect the X2 harness connector at the K8A Blower Motor Control Module - Auxiliary and disconnect the harness connector at the M8B Blower Motor - Auxiliary. Test for infinite resistance between the M8B Blower Motor - Auxiliary B+ circuit terminal B and ground. If less than infinite resistance, repair the short to ground on the circuit. If infinite resistance, test or replace the M8B Blower Motor - Auxiliary. If the test lamp illuminates
5. Remove the test lamp.
6. Verify the resistance between the control circuit terminal 1 and ground varies from 100 ohms to 90K ohms while changing blower speeds. If the resistance does not change from 100 ohms to 90K ohms Ignition OFF, disconnect the X2 harness connector at the K33 HVAC Control Module, ignition ON. Test for less than 1 V between the control circuit and ground. If 1 V or greater, repair the short to voltage on the circuit. If less than 1 V Test for infinite resistance between the control circuit and ground. If less than infinite resistance, repair the short to ground on the circuit. If infinite resistance. Test for less than 2 ohms in the control circuit end to end. If 2 ohms or greater, repair the open/high resistance in the circuit. If less than 2 ohms replace the K33 HVAC Control Module. If the resistance does change from 100 ohms to 90K ohms
7. Ignition OFF, connect the X1 harness connector at the K8A Blower Motor Control Module - Auxiliary and disconnect the harness connector at the M8B Blower Motor - Auxiliary, ignition ON and blower ON.
8. Verify a test lamp illuminates between the B+ terminal B and ground. If the test lamp does not illuminate Ignition OFF, disconnect the X2 harness connector at the K8A Blower Motor Control Module - Auxiliary. Test for less than 2 ohms in the B+ circuit end to end. If 2 ohms or greater, repair the open/high resistance in the circuit. If less than 2 ohms replace the K8A Blower Motor Control Module - Auxiliary. If the test lamp illuminates
9. Connect a test lamp between the B+ circuit terminal B and control circuit terminal A, ignition ON.
10. Verify the test lamp becomes progressively brighter as the blower speed is increased and progressively dimmer as the blower speed is decreased. If the test lamp does not illuminate Ignition OFF, remove the test lamp and disconnect the X2 harness connector at the K8A Blower Motor Control Module - Auxiliary, ignition ON. Test for less than 1 V between the control circuit terminal A and ground. If 1 V or greater, repair the short to voltage on the circuit. If less than 1 V Test for less than 2 ohms in the control circuit end to end. If 2 ohms or greater, repair the open/high resistance in the circuit. If less than 2 ohms replace the K8A Blower Motor Control Module - Auxiliary. If the test lamp illuminates, but does not change in brightness Ignition OFF, remove the test lamp and disconnect the X2 harness connector at the K8 Blower Motor Control Module. Test for infinite resistance between the control circuit terminal A and ground. If less than infinite resistance, repair the short to ground on the circuit. If infinite resistance, replace the K8A Blower Motor Control Module - Auxiliary. If the test lamp changes in brightness as the blower speed is changed
11. Test or replace the M8B Blower Motor - Auxiliary.

1. Perform the «Diagnostic System Check - Vehicle»(ref-644698-S03753758692014072300000) prior to using this diagnostic procedure.
2. Review «Strategy Based Diagnosis»(ref-644698-S14897089332014072300000) for an overview of the diagnostic approach.
3. «Diagnostic Procedure Instructions»(ref-644698-S14982480842014072300000) provides an overview of each diagnostic category.

1. Ignition ON.
2. The HVAC control module is ON.

B023A 02

The stepper motor supply output is shorted to ground.

B0223 01, B022A 01, B0233 01, B0408 01, B0418 01, B0428 01 or B3531 01

At least one of the stepper motor control circuits is shorted to voltage when motor starts moving. Faults are not detected when motor is already running or target position is already reached.

B0223 06, B022A 06, B0233 06, B0408 06, B0418 06, B0428 06 or B3531 06

At least one of the stepper motor control circuits is shorted to ground or open when motor starts moving. Faults are not detected when motor is already running or target position is already reached.

B023A 02

1. The affected output will be switched off for hardware protection.
2. All stepper motors are deactivated.

B0223, B022A, B0233, B0408, B0418, B0428 or B3531

1. The affected output will be switched off for hardware protection.
2. The affected stepper motor is deactivated.

The condition for setting the DTC is no longer present.

DTC B023A

1. Ignition OFF and all vehicle systems OFF, disconnect the harness connector at the components listed below. It may take up to 2 min for all vehicle systems to power down. M4 Air Inlet Door Actuator M37 Mode Door Actuator M46 Air Recirculation Door Actuator M6L Air Temperature Door Actuator - Left M6R Air Temperature Door Actuator - Right M37B Mode Door Actuator - Auxiliary M6B Air Temperature Door Actuator - Auxiliary
2. Disconnect the X3 and X4 harness connectors at the K33 HVAC Control Module.
3. Test for infinite resistance between the K33 HVAC Control Module 12 V reference circuit terminal 15 X3 and ground. If less than infinite resistance Repair the short to ground on the circuit. If infinite resistance
4. Ignition ON.
5. Test for less than 1 V between the K33 HVAC Control Module 12 V reference circuit terminal 15 X3 and ground. If 1 V or greater Repair the short to voltage on the circuit. If less than 1 V
6. Connect the X3 and X4 harness connectors at the K33 HVAC Control Module, ignition ON.
7. Clear all DTCs.
8. Verify DTC B023A is not set. If the DTC is set. Replace the K33 HVAC Control Module. If the DTC is not set.
9. Verify DTC B023A does not set after connecting each of the components listed below one at a time and operating them through their full range. M4 Air Inlet Door Actuator M37 Mode Door Actuator M46 Air Recirculation Door Actuator M6L Air Temperature Door Actuator - Left M6R Air Temperature Door Actuator - Right M37B Mode Door Actuator - Auxiliary M6B Air Temperature Door Actuator - Auxiliary If the DTC sets Replace the component that was connected immediately before the DTC set. If the DTC does not set
10. All OK.

DTC B0223, B022A, B0233, B0408, B0418, B0428 or B3531

1. Ignition OFF, disconnect the harness connector at the appropriate door actuator, ignition ON.
2. Verify a test lamp flashes when connected between the 12 V reference circuit terminal 2 and ground. If the test lamp does not flash Ignition OFF, remove the test lamp and disconnect the harness connector at the K33 HVAC Control Module. Test for less than 2 ohms in the 12 V control circuit end to end. If 2 ohms or greater, repair the open/high resistance in the circuit. If less than 2 ohms, replace the K33 HVAC Control Module. If the test lamp flashes
3. Connect a test lamp between each control circuit listed below and B+. Control Circuit - terminal 1 Control Circuit - terminal 3 Control Circuit - terminal 4 Control Circuit - terminal 6
4. Command the appropriate door actuator in both directions.
5. Verify the test lamp turns ON and then OFF during at least one of the directional commands. If the test lamp is always ON Ignition OFF, remove the test lamp and disconnect the harness connector at the K33 HVAC Control Module. Test for infinite resistance between the control circuit 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 the test lamp is always OFF Ignition OFF, remove the test lamp and disconnect the harness connector at the K33 HVAC Control Module, ignition ON. Test for less than 1 V between the control circuit and ground. If 1 V or greater, repair the short to voltage on the circuit. If less than 1 V Ignition OFF Test for less than 2 ohms in the control circuit end to end. If 2 ohms or greater, repair the open/high resistance is the circuit. If less than 2 ohms, replace the K33 HVAC Control Module. If the test lamp turns ON and then OFF
6. Test or replace the door actuator.

1. Perform the «Diagnostic System Check - Vehicle»(ref-644698-S03753758692014072300000) prior to using this diagnostic procedure.
2. Review «Strategy Based Diagnosis»(ref-644698-S14897089332014072300000) for an overview of the diagnostic approach.
3. «Diagnostic Procedure Instructions»(ref-644698-S14982480842014072300000) provides an overview of each diagnostic category.

1. Ignition is ON or in the ACC position.
2. The system voltage is at least 9.5 V and no more than 15.5 V.
3. All the above conditions are present for greater than 10 seconds.

The HVAC control module receives an improper status response indicating an internal ECU fault in the HVAC control module - auxiliary.

No action is taken.

1. A current DTC clears when the HVAC control module receives a proper status response message back from the HVAC control module - auxiliary assembly.
2. A history DTC clears after 50 malfunction-free ignition cycles.

1. This DTC may be stored as a history DTC without affecting the operation of the HVAC control module - auxiliary.
2. If stored only as a history DTC and not retrieved as a current DTC, do not replace the HVAC control module - auxiliary.
3. If this DTC is retrieved as both a current and history DTC, replace the HVAC control module - auxiliary.

1. Perform the «Diagnostic System Check - Vehicle»(ref-644698-S03753758692014072300000) prior to using this diagnostic procedure.
2. Review «Strategy Based Diagnosis»(ref-644698-S14897089332014072300000) for an overview of the diagnostic approach.
3. «Diagnostic Procedure Instructions»(ref-644698-S14982480842014072300000) provides an overview of each diagnostic category.

1. Ignition ON
2. The HVAC control module is ON.

B3843 02

No PWM is detected and the signal is low.

B3843 05

No PWM is detected and the signal is high.

B3843 08

The sensor sends a 5% PWM signal indicating an internal sensor short circuit or open circuit.

The automatic recirculation mode is disabled.

The condition for setting the DTC is no longer present.

1. Ignition OFF and all vehicle systems OFF, disconnect the harness connector at the B108 Air Quality Sensor. It may take up to 2 min for all vehicle systems to power down.
2. Test for less than 10 ohms between the ground circuit terminal 2 and ground. If 10 ohms or greater Ignition OFF. Test for less than 2 ohms in the ground circuit end to end. If 2 ohms or greater, repair the open/high resistance in the circuit. If less than 2 ohms, repair the open/high resistance in the ground connection. If less than 10 ohms
3. Ignition ON.
4. Verify a test lamp illuminates between the ignition circuit terminal 1 and ground. If the test lamp does not illuminate and the circuit fuse is good Ignition OFF, remove the test lamp. Test for less than 2 ohms in the ignition circuit end to end. If 2 ohms or greater, repair the open/high resistance in the circuit. If less than 2 ohms, verify the fuse is OK and there is voltage at the fuse. If the test lamp does not illuminate and the circuit fuse is open Ignition OFF, remove the test lamp. Test for infinite resistance between the ignition circuit and ground. If less than infinite resistance, repair the short to ground on the circuit. If infinite resistance, replace the B108 Air Quality Sensor. If the test lamp illuminates
5. Install a test lamp between the signal circuit terminal 3 and the ignition circuit terminal 1. NOTE: This connection may need to be in place for nearly 60 seconds before there is a change in the parameter.
6. Verify the scan tool Air Quality Sensor parameter is greater than 95%. If the parameter is 95% or less Ignition OFF, remove the test lamp and disconnect the harness connector at the K33 HVAC Control Module. 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 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 K33 HVAC Control Module. If the parameter is greater than 95%
7. Remove the test lamp and Install a 3 A fused jumper wire between the signal circuit terminal 3 and the ground circuit terminal 2. NOTE: This connection may need to be in place for nearly 60 seconds before there is a change in the parameter.
8. Verify the scan tool Air Quality Sensor parameter is less than 5%. If the parameter is 5% or greater Ignition OFF, remove the jumper wire and disconnect the harness connector at the K33 HVAC Control Module, ignition ON. 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 Ignition OFF 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 K33 HVAC Control Module. If the parameter is less than 5%
9. Replace the B108 Air Quality Sensor.

1. Perform the «Diagnostic System Check - Vehicle»(ref-644698-S03753758692014072300000) prior to using this diagnostic procedure.
2. Review «Strategy Based Diagnosis»(ref-644698-S14897089332014072300000) for an overview of the diagnostic approach.
3. «Diagnostic Procedure Instructions»(ref-644698-S14982480842014072300000) provides an overview of each diagnostic category.

DTC Descriptor

For symptom byte information, refer to Symptom Byte List .

1. Ignition ON.
2. The HVAC control module is ON.

B393B 04

A PWM greater than 10% is sent but no current is read back.

B393B 0B

Measured current is above threshold of 815 mA.

B393B 04

The A/C compressor is disabled.

B393B 0B

1. The A/C compressor is disabled.
2. Output will be switched off for hardware protection.

The condition for setting the DTC is no longer present.

1. Ignition OFF, disconnect the harness connector at the Q46 A/C Compressor Solenoid Valve, ignition ON.
2. Verify a test lamp illuminates between the B+ circuit terminal 2 and ground. If the test lamp does not illuminate Ignition OFF, remove the test lamp and disconnect the harness connectors at the K33 HVAC Control Module. Test for infinite resistance between the Q46 A/C Compressor Solenoid Valve B+ circuit terminal 2 and ground. If less than infinite resistance, repair the short to ground on the circuit. If infinite resistance. Test for less than 2 ohms in the B+ circuit end to end. If 2 ohms or greater, repair the open/high resistance in the circuit. If less than 2 ohms, replace the K33 HVAC Control Module. If the test lamp illuminates
3. Ignition OFF, connect a test lamp between the control circuit terminal 1 and the B+ circuit terminal 2, ignition ON.
4. Verify the test lamp turns ON and OFF when commanding the Q46 A/C Compressor Refrigerant Solenoid Valve On and Off with a scan tool. If the test lamp is always OFF Ignition OFF, remove the test lamp and disconnect the harness connectors at the K33 HVAC Control Module, ignition ON. Test for less than 1 V between the Q46 A/C Compressor Refrigerant Solenoid Valve control circuit terminal 1 and ground. If 1 V or greater, repair the short to voltage on the circuit. If less than 1 V Ignition OFF. Test for less than 2 ohms in the control circuit end to end. If 2 ohms or greater, repair the open/high resistance in the circuit. If less than 2 ohms, replace the K33 HVAC Control Module. If the test lamp is always ON Ignition OFF, remove the test lamp and disconnect the harness connectors at the K33 HVAC Control Module. Test for infinite resistance between the Q46 A/C Compressor Refrigerant Solenoid Valve control circuit terminal 1 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 the test lamp turns ON and OFF
5. Test or replace the G1 A/C Compressor.

Component Testing

A/C Compressor Solenoid Valve Test

1. Ignition OFF, disconnect the harness connector at the Q46 A/C Compressor Solenoid Valve.
2. Test for 7-15 ohms between B+ terminal 2 and control terminal 1. If less than 7 ohms or greater than 15 ohms Replace the G1 A/C Compressor. If between 7-15 ohms
3. Test for infinite resistance between each terminal and the Q46 A/C Compressor Solenoid Valve housing/case. If less than infinite resistance Replace the G1 A/C Compressor. If infinite resistance
4. All OK.

1. Perform the «Diagnostic System Check - Vehicle»(ref-644698-S03753758692014072300000) prior to using this diagnostic procedure.
2. Review «Strategy Based Diagnosis»(ref-644698-S14897089332014072300000) for an overview of the diagnostic approach.
3. «Diagnostic Procedure Instructions»(ref-644698-S14982480842014072300000) provides an overview of the diagnostic category.

1. Engine is running.
2. Any of the conditions for setting the DTC are met for 15 s.
3. Battery voltage is between 11-18 V.

P0532

The ECM detects that the A/C pressure is less than 1 psi (0.25 V).

P0533

The ECM detects that the A/C pressure is more than 428 psi (4.92 V).

1. The A/C compressor is disabled.
2. The ECM will illuminate the malfunction indicator lamp (MIL).

The condition for setting the DTC is no longer present.

A malfunction within the refrigerant system causing high pressure can cause this DTC to set.

1. Ignition OFF and all vehicle systems OFF, disconnect the harness connector at the B1 A/C Refrigerant Pressure Sensor. It may take up to 2 min for all vehicle systems to power down.
2. Test for less than 10 ohms between the low reference circuit terminal 1 and ground. If 10 ohms or greater Ignition OFF, disconnect the harness connector at the K20 Engine Control Module. 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 K20 Engine Control Module. If less than 10 ohms
3. Ignition ON.
4. Test for 4.8-5.2 V between the 5 V reference circuit terminal 2 and ground. If less than 4.8 V Ignition OFF, disconnect the harness connector at the K20 Engine Control Module. Test for infinite resistance between the 5 V reference circuit and ground. If less than infinite resistance, repair the short to ground on the circuit. If infinite resistance Test for less than 2 ohms in the 5 V 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 K20 Engine Control Module. If greater than 5.2 V Ignition OFF, disconnect the harness connector at the K20 Engine Control Module, ignition ON. Test for less than 1 V between the 5 V reference circuit and ground. If 1 V or greater, repair the short to voltage on the circuit. If less than 1 V, replace the K20 Engine Control Module. If between 4.8-5.2 V
5. Verify the scan tool A/C High Side Pressure Sensor parameter is less than .25 V. If .25 V or greater Ignition OFF, disconnect the harness connector at the K20 Engine Control Module, ignition ON. Test for less than 1 V between the signal circuit terminal 3 and ground. If 1 V or greater, repair the short to voltage on the circuit. If less than 1 V, replace the K20 Engine Control Module. If less than .25 V
6. Install a 3 A fused jumper wire between the signal circuit terminal 3 and the 5 V reference circuit terminal 2.
7. Verify the scan tool A/C High Side Pressure Sensor parameter is greater than 4.8 V. If 4.8 V or less Ignition OFF, remove the jumper wire, disconnect the harness connector at the K20 Engine Control Module. 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 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 K20 Engine Control Module. If greater than 4.8 V
8. Test or replace the B1 A/C Refrigerant Pressure Sensor.

1. Perform the «Diagnostic System Check - Vehicle»(ref-644698-S03753758692014072300000) prior to using this diagnostic procedure.
2. Review «Strategy Based Diagnosis»(ref-644698-S14897089332014072300000) for an overview of the diagnostic approach.
3. «Diagnostic Procedure Instructions»(ref-644698-S14982480842014072300000) provides an overview of each diagnostic category.

1. Engine is running.
2. The HVAC control module is ON.
3. The A/C switch is active.

P0645 or P0646

The ECM detects a short to ground or an open at the A/C compressor clutch relay control circuit.

P0647

The ECM detects a short to voltage at the A/C compressor clutch relay control circuit.

P0645 or P0646

The A/C compressor is inoperative or always active. The A/C compressor solenoid is commanded to 0% displacement. This causes warm air from the ducts, even with unwanted clutch engagement.

P0647

The A/C compressor is inoperative.

The condition for setting the DTC is no longer present.

1. Ignition OFF, disconnect the KR29 A/C Compressor Clutch Relay, ignition ON.
2. Verify a test lamp illuminates between the B+ circuit terminal 30 and ground. If the test lamp does not illuminate and the circuit fuse is good Ignition OFF, remove the test lamp. Test for less than 2 ohms in the B+ circuit end to end. If 2 ohms or greater, repair the open/high resistance in the circuit. If less than 2 ohms, verify the fuse is not open and there is voltage at the fuse. If the test lamp does not illuminate and the circuit fuse is open Ignition OFF, remove the test lamp. Test for infinite resistance between the B+ circuit and ground. If less than infinite resistance, repair the short to ground on the circuit. If infinite resistance Disconnect the harness connector at the Q2 A/C Compressor Clutch. Test for infinite resistance between the control circuit terminal 87 and ground. If less than infinite resistance, repair the short to ground on the circuit. If infinite resistance, test or replace the Q2 A/C Compressor Clutch. If the test lamp illuminates
3. Ignition ON.
4. Verify a test lamp illuminates between the ignition circuit terminal 85 and ground. If the test lamp does not illuminate Refer to «Power Mode Mismatch»(ref-644726-S20060898812014072300000) . If the test lamp illuminates
5. Connect a test lamp between the ignition circuit terminal 85 and the control circuit terminal 86.
6. Verify the test lamp turns ON and OFF when commanding the ECM A/C Compressor Clutch Relay On and Off with a scan tool. If the test lamp is always OFF Ignition OFF, remove the test lamp and disconnect the harness connector at the K20 Engine Control Module, ignition ON. Test for less than 1 V between the control circuit and ground. If 1 V or greater, repair the short to voltage on the circuit. If less than 1 V Ignition OFF. Test for less than 2 ohms in the control circuit end to end. If 2 ohms or greater, repair the open/high resistance in the circuit. If less than 2 ohms, replace the K20 Engine Control Module. If the test lamp is always ON Ignition OFF, remove the test lamp and disconnect the harness connector at the K20 Engine Control Module. Test for infinite resistance between the control circuit and ground. If less than infinite resistance, repair the short to ground on the circuit. If infinite resistance, replace the K20 Engine Control Module. If the test lamp turns ON and OFF
7. Verify a test lamp does not illuminate between the control circuit terminal 87 and ground. If the test lamp illuminates Repair the short to voltage on the circuit. If the test lamp does not illuminate
8. Ignition OFF and all vehicle systems OFF, disconnect the harness connector at the Q2 A/C Compressor Clutch. It may take up to 2 min for all vehicle systems to power down.
9. Test for less than 10 ohms between the ground circuit terminal 1 and ground. If 10 ohms or greater Ignition OFF. Test for less than 2 ohms in the ground circuit end to end. If 2 ohms or greater, repair the open/high resistance in the circuit. If less than 2 ohms, repair the open/high resistance in the ground connection. If less than 10 ohms
10. Connect the harness connector at the Q2 A/C Compressor Clutch.
11. Ignition ON, connect a 10 A fused jumper wire between the B+ circuit terminal 30 and the control circuit terminal 87.
12. Verify the Q2 A/C Compressor Clutch is engaged. If the Q2 A/C Compressor Clutch does not engage Ignition OFF, disconnect the harness connector at the Q2 A/C Compressor Clutch. Test for less than 2 ohms in the control circuit end to end. If 2 ohms or greater, repair the open/high resistance in the circuit. If less than 2 ohms, test or replace the Q2 A/C Compressor Clutch. If the Q2 A/C Compressor Clutch is engaged
13. Test or replace the KR29 A/C Compressor Clutch Relay.

1. Ignition OFF, disconnect the KR29 A/C Compressor Clutch Relay.
2. Test for 60-180 ohms between terminals 85 and 86. If not between 60-180 ohms Replace the KR29 A/C Compressor Clutch Relay. If between 60-180 ohms
3. Test for infinite resistance between the terminals listed below: 30 and 86 30 and 87 30 and 85 85 and 87 If less than infinite resistance Replace the KR29 A/C Compressor Clutch Relay. If infinite resistance
4. Install a 15 A fused jumper wire between terminal 86 and 12 V. Install a jumper wire between terminal 85 and ground.
5. Test for less than 2 ohms between terminals 30 and 87. If 2 ohms or greater Replace the KR29 A/C Compressor Clutch Relay. If less than 2 ohms
6. All OK.

Visual/Physical Inspection

1. Inspect for aftermarket devices which may affect the operation of the Steering Wheel Controls System. Refer to «Checking Aftermarket Accessories»(ref-644726-S15551717792014072300000) .
2. Inspect for easily accessible or visible system components for obvious damage or conditions which may cause the symptom.

Symptom List

Refer to HVAC System Malfunction in order to diagnose the symptom.

1. Perform the «Diagnostic System Check - Vehicle»(ref-644698-S03753758692014072300000) prior to using this diagnostic procedure.
2. Review «Strategy Based Diagnosis»(ref-644698-S14897089332014072300000) for an overview of the diagnostic approach.
3. «Diagnostic Procedure Instructions»(ref-644698-S14982480842014072300000) provides an overview of each diagnostic category.

Check the following mechanical fault sources

1. Air distribution box
2. Air distribution hoses/air distribution ducts

1. Perform the «Diagnostic System Check - Vehicle»(ref-644698-S03753758692014072300000) prior to using this diagnostic procedure.
2. Review «Strategy Based Diagnosis»(ref-644698-S14897089332014072300000) for an overview of the diagnostic approach.
3. «Diagnostic Procedure Instructions»(ref-644698-S14982480842014072300000) provides an overview of each diagnostic category.

The following conditions must be met in order to turn on the A/C compressor

1. Battery voltage is between 9-18 V.
2. Engine coolant temperature is less than 124°C (255°F).
3. Engine speed is greater than 600 RPM.
4. Engine speed is less than 5 500 RPM.
5. A/C high side pressure is between 269-2 929 kPa (39-425 PSI).
6. Throttle position is less than 100%.
7. Evaporator temperature is greater than 3°C (38°F).
8. ECM does not detect excessive torque load.
9. ECM does not detect insufficient idle quality.
10. The ambient temperature is above 1°C (34°F).
11. Blower motor is ON.