Air Conditioner Diagnostic Trouble Codes (Chevrolet Captiva 1)

• Code B0163 Short to Battery or Open Front PCAT Sensor Input Voltage Circuit
• Code B0163 Front PCAT Sensor Input Voltage Circuit Short to Ground or Open

• The HVAC controller detects that the air temperature parameter value is less than 0.27 V or greater than 4.64 V.
• The HVAC controller detects a short to battery positive in the in-cabin sensor or PCAT sensor circuit.
• The HVAC controller detects an open in the in-cabin sensor or PCAT sensor control circuit.

• The fault code will be transferred to the log if the HVAC controller no longer detects a fault.
• Ignition to the "ON" or "OFF" position.
• The fault code can be cleared using a diagnostic tool.

3. The resistance of the interior sensor or PCAT sensor is checked (2.2 kOhm at 25°C).
6. Checks the voltage supplied to the in-cabin sensor or PCAT sensor from the HVAC controller (2.2 V at 25°C)

• Code B0173 Short to battery or open in air duct sensor input voltage circuit
• Code B0173 Air Duct Sensor Input Voltage Short to Ground or Open

• The HVAC controller detects that the air temperature parameter value is less than 0.27 V or greater than 4.64 V.
• The HVAC controller detects a short to battery positive in the air duct sensor circuit.
• The HVAC controller detects an open in the air duct sensor control circuit.

• The fault code will be transferred to the log if the HVAC controller no longer detects a fault.
• Ignition to the "ON" or "OFF" position.
• The fault code can be cleared using a diagnostic tool.

6. The air duct sensor voltage is checked (2.2 V at 25°C).
7. The resistance of the air duct sensor is checked (2.2 kOhm at 25°C)

• Code B0183 Short to battery voltage or open circuit in the front left solar radiation sensor.
• Code B0183 Short to ground or open circuit in front left solar radiation sensor circuit.

• The HVAC controller detects that the sun sensor parameter value is less than 0.20 V or greater than 4.64 V.
• The HVAC controller detects a short to battery positive in the solar radiation sensor circuit.
• The HVAC controller detects an open in the solar sensor control circuit.

• The fault code will be transferred to the log if the HVAC controller no longer detects a fault.
• Ignition to the "ON" or "OFF" position.
• The fault code can be cleared using a diagnostic tool.

9. The current at the HVAC controller output is checked. (In direct sunlight: 3.2V, in shade: 4.0V)

• Code B0193 Short to battery voltage or open circuit in the power module.
• Code B0193 Short to ground or open circuit in the power module.

• The operating voltage of the electric fan is below 5.0 V (actual feedback voltage of the electric fan), above 9.0 V operating voltage of the electric fan.
• The operating voltage of the electric fan is higher than 9.0 V (actual feedback voltage of the electric fan), below 5.0 V of the working voltage of the electric fan.
• The HVAC controller detects an open or short in the blower motor control circuit.

• The fault code will be transferred to the log if the HVAC controller no longer detects a fault.
• Ignition to the "ON" or "OFF" position.
• The fault code can be cleared using a diagnostic tool.

4. The voltage of the electric fan levels is checked from the lower to the higher level, and the voltage of all levels is increased by 0.5 V.

• Code B0228 Short to battery voltage or open in the air intake flap feedback voltage circuit.
• Code B0228 Short to ground or open in air intake flap feedback voltage circuit.
• Code B0228 Invalid air intake flap feedback signal.

• Ignition in the "ON" position.

• The feedback voltage of the intake valve actuator is below 0.20 V.
• The feedback voltage of the intake valve actuator is higher than 4.8 V.
• The position value of the intake flap actuator corresponds to an unattainable position.

• The fault code will be transferred to the log if the HVAC controller no longer detects a fault.
• Ignition to the "ON" or "OFF" position.
• The fault code can be cleared using a diagnostic tool.

1. Ignition switch in the "ON" position
2. Check the ignition voltage (12 V) and the voltage of the electric motor (5 V) of the air intake flap drive.
3. Check the reference level of the air intake flap actuator.

• Code B0283 Electric heated rear window

• The Body Control Module (BCM) stores a code B0283 in its memory. The heated glass will not operate.

• The current fault code is cleared once the fault has disappeared.
• The fault code is cleared from the history when the ignition cycle counter in the controller reaches the reset threshold without the fault recurring.

2. Check the positive battery voltage on the rear window heating relay coil side. Voltage is supplied to the DEFOG relay coil side via fuse EF25 (10 A).
3. Check the DEFOG relay control circuit for faults that could cause DTC B0283 to be set.
4. Listen to the click when the DEFOG relay is triggered. Issue a command to turn on and off. Repeat the commands if necessary.
5. Check that the body control module (BCM) grounds the heated glass relay.

• Code B0413 Short to battery voltage or open circuit in the air mix flap feedback voltage circuit.
• Code B0413 Short to ground or open in the air mix flap feedback voltage circuit.
• Code B0413 Invalid air mix flap feedback signal.

• The feedback voltage of the air mixing flap actuator is below 0.20 V.
• The feedback voltage of the air mixing flap actuator is higher than 4.8 V.
• The position value of the air mixing flap electric drive corresponds to an unattainable position.

• The fault code will be transferred to the log if the HVAC controller no longer detects a fault.
• Ignition to the "ON" or "OFF" position.
• The fault code can be cleared using a diagnostic tool.

2. The ignition switch is in the "ON" position.
3. The ignition switch is in the "ON" position.
4. Check the ignition voltage (12 V) and the voltage of the electric motor (5 V) of the air intake flap drive.
5. Check the reference level of the air intake flap actuator.

• The ignition switch is in the "ON" position.

• The HVAC controller detects a faulty ROM.

• The HVAC controller records operating conditions when a fault occurs during diagnostics. This information will be stored in the Freeze Frame and Fault Records buffers.
• The fault code is stored in the log.

• The fault code is cleared from the history after 40 consecutive warm-up cycles in which there was no fault.
• The fault code(s) can be cleared using a diagnostic tool.
• Disconnect the HVAC controller from battery power for 10 seconds

• Code B3779 Short to battery voltage or open circuit in the feedback voltage circuit of the mode flap actuator.
• Code B3779 Short to ground or open circuit in the feedback voltage circuit of the mode throttle actuator.
• Code B3779 Invalid feedback signal from the mode flap actuator.

• The feedback voltage of the mode flap actuator is below 0.20 V.
• The feedback voltage of the mode flap actuator is higher than 4.8 V.
• The position value of the electric drive of the mode damper corresponds to an unattainable position.

• The fault code will be transferred to the log if the HVAC controller no longer detects a fault.
• Ignition to the "ON" or "OFF" position.
• The fault code can be cleared using a diagnostic tool.

2. The ignition switch is in the "ON" position.
3. The ignition switch is in the "ON" position.
4. Check the ignition voltage (12 V) and the voltage of the electric motor (5 V) of the air intake flap drive.
5. Check the reference level of the air intake flap actuator.

• Code B3843 Short to battery voltage or open circuit in outside air quality sensor input voltage.
• Code B3843 Outside Air Quality Sensor Input Voltage Circuit Short to Ground.

• Ignition in the "ON" position.

• APS sensor feedback voltage is below 0.05V.
• APS sensor feedback voltage is greater than 4.79V.

• The APS sensor does not function.
• APS LED is not lit.

• The fault code will be transferred to the log if the HVAC controller no longer detects a fault.
• The fault code can be cleared using a diagnostic tool.
• Disconnect the HVAC controller from battery power for 10 seconds

2. The APS sensor voltage is checked. (In the range 0 - 5 V)
3. The ignition switch is in the "ON" position, and the voltage is checked at terminals A16 and A9 of the HVAC controller connector.

• The ignition is turned to the "ON" position.

• Segment lights up on HVAC controller "A/C OFF" ("the air conditioner is turned off").
• The air conditioning compressor switches off.

• The fault code will be transferred to the log if the HVAC controller no longer detects a fault.
• The fault code in the history will be cleared after 50 ignition cycles without a fault.
• The fault code can be cleared using a diagnostic tool.

3. During this operation, the correct operation of the circuit in the upper voltage range is checked.
4. This operation checks for proper operation of the circuit in the lower voltage range. If the fuse on the jumper blows during this test, there is a short to supply voltage in the signal circuit.

• Using the communication line list, identify the GMLAN low speed serial communication line controllers.
• This test is used for the general GMLAN Low Speed Communication Failure fault. If there is no communication with only 1 controller and the fault code is not set, make sure the vehicle is equipped with such a controller, then diagnose the U0100-U0299 code.
• Open circuit in low speed GMLAN serial communication line between terminal block and controller (controllers) will only affect a specific controller (controllers). This type of fault will result in a data communication failure code being entered for each affected controller, while other controllers will still communicate.
• Opening the DLC ground circuit terminal 5 will allow the scan tool to operate to learn the vehicle and then stop communicating with the vehicle. When the scan tool has essentially established communication with the vehicle, the scan tool will display the message "No CANdi module detected" (CANdi controller not found) and there will be no data exchange.
• An open circuit between the data link connector (DLC) and the C 203 connector will only affect communication with the diagnostic tool. The vehicle controllers will still communicate and the vehicle will start.
• The engine will not start if a general low speed GMLAN serial communication circuit fault is present. The following conditions may cause a general low speed GMLAN serial communication circuit failure:
• Short to ground or open circuit in the low speed GMLAN serial data line.
• An internal controller fault causes a short to voltage or ground on the low speed GMLAN line.
• To localize an intermittent fault, use the MIN/MAX function of the multimeter.

1. Check that the resistance between terminal 5 of the DLC connector ground circuit and ground is no more than 1 ohm.
• If the resistance is greater than 1 ohm, check the ground circuit for an open or high resistance.
2. Turn off the ignition, disconnect the wiring harness connector at the SP 300 terminal block.
3. Turn on ignition, using the diagnostic tool try to establish communication with the instrument cluster (IPC). Communication should be available.
• If communication is not possible, disconnect the controllers still connected to the DLC one at a time, starting with the one farthest from the DLC, and attempt to establish communication after each disconnection. If communication is established, test the serial data line for a short to ground and a short to voltage in the circuit between the last controller disconnected and the previous controller disconnected. If the circuit is good, replace the last controller disconnected. If communication is not possible, test the serial data line for a short to ground, short to voltage, or open/high resistance in the circuit between the last controller disconnected and the DLC. If the circuit is good, replace the last controller disconnected.
4. Install a jumper wire with a 3-amp fuse between pin A and pin M of the terminal block. Install another jumper wire with a 3-amp fuse on pin L.
5. Using the open end of the jumper on pin L, connect terminals B - K of the terminal block and attempt to communicate with each controller connected to the terminal block one at a time. Each controller should be able to transmit data.
• If communication with any controller fails after connecting a separate controller, replace the controller that is causing the communication failure.

• Information on the controller for replacement, setup and programming.

1. The supply voltage of the controllers is within the normal operating range.
2. The vehicle's power mode requires data exchange via a serial communication line.

• The controller stops transmitting all commands.
• The controller uses standard values for all parameters received via serial communication lines.
• The controller prohibits the setting of all other fault codes.

• The current fault code is cleared once the fault has disappeared.
• The fault code is cleared from the history when the ignition cycle counter in the controller reaches the reset threshold of 50 cycles without a recurrence of the fault.

• An intermittent fault may be caused by a short in the high speed GMLAN communication lines.
• This DTC cannot be retrieved with the current status.
• The diagnostic for the "Screen scan tool cannot communicate with a device on the high speed GMLAN" symptom is being performed.
• Specific controllers that use the high speed GMLAN communication line are listed in the Communication Lines List.

1. The voltage in the system is 9 - 16 V.
2. The vehicle power mode master device requires serial data exchange to operate.

• The current fault code is cleared once the fault has disappeared.
• The fault code is cleared from the history when the ignition cycle counter in the controller reaches the reset threshold of 50 cycles without a recurrence of the fault.

• Using the above list of fault code definitions, determine which controller is experiencing communication problems.
• If there are multiple controllers with communication problems, select the one closest to the diagnostic connector (DLC).
• Using the communication line list, determine whether the GMLAN serial communication line used on the controller is high speed or low speed.
• Some controllers do not have internal protection for certain voltage outputs and may cause the battery positive voltage fuse or ignition voltage supply to blow. If the input voltage fuse is blown but no short circuit is detected in that circuit, make sure there are no shorted to ground voltage output circuits on the controllers before replacing the controller.
• This diagnostic can be used on any module that is required to communicate over the high or low speed GMLAN serial data line, provided the vehicle is equipped with an option that uses that module.

1. Use the above list of fault code definitions and diagnostic recommendations to determine which controller with the communication problem needs to be tested.
2. Turn off the ignition, disconnect the wiring harness connector on the controller where the connection is broken.

Important: Only high speed GMLAN controllers have a serial communications enable circuit OR an auxiliary serial communications wake-up circuit. Refer to the controller schematics to determine which controllers have these circuits. If the controller with the communication problem is missing one of these circuits, go to Step 4.

3. Turn ignition ON, verify that the test lamp illuminates between the serial data line enable circuit OR the auxiliary serial data line wake-up circuit and ground.
• If the test lamp does not light, repair the open or high resistance in the circuit. If there are no faults in the circuits, replace the BCM.
• If the test lamp does not light, eliminate the short to ground or open/high resistance in the circuit. If the circuit fuse is blown, also check the positive voltage outputs on the controller for a short to ground. If the circuits are OK, replace the faulty controller.
• If the test lamp does not light, eliminate the short to ground or open/high resistance in the circuit. If the circuit fuse is blown, also check the positive voltage outputs on the controller for a short to ground. If the circuits are OK, replace the faulty controller.
• If it is higher than 1 Ohm, repair the open circuit in the ground circuit.
• If the controller uses only high speed GMLAN communication line, replace the controller.
• If the resistance is greater than 1 ohm, test the low speed GMLAN serial data circuit for an open or high resistance.

• Information on the controller for replacement, setup and programming.
• GMLAN wiring repair