:  Dec 17, 2007



Overview

The heating and ventilation system is a fairly straightforward design requiring no specialized techniques for diagnosis.

Follow the visual inspection below and refer to the diagnostic trouble code (DTC) index for electrical faults.

For information on the description and operation of the system, refer to the relevant section of the workshop manual.

Inspection and Verification

. Verify the customer concern.

. Visually inspect for obvious mechanical or electrical faults.

Mechanical Electrical
  • Intake ducts blocked/restricted
  • Coolant level
  • Air in cooling system
  • Distribution motors and flaps
  • Fuses
  • Harnesses and connectors
  • Blower relay
  • Blower control module
  • Blower assembly
  • Automatic temperature control module

. If an obvious cause for an observed or reported concern is found, correct the cause (if possible) before proceeding to the next step

. Use the approved diagnostic system or a scan tool to retrieve any DTCs before moving onto the symptom chart or DTC index.
  Make sure that all DTCs are cleared following rectification.
Make sure that all DTCs are cleared following rectification.

Symptom chart

Symptom Possible causes Action
Air intake stuck in one position
  • Sensor fault
  • Distribution motor fault
Check for DTCs indicating a sensor fault (refer to the DTC index below). Carry out the distribution motor self-test. Refer to the relevant section of the workshop manual.
Excessive blower noise
  • Blower mechanical fault
  • Debris drawn into the blower
  • Solar sensor fault
Check for mechanical faults/debris in the blower motor or fixings. Check for DTCs indicating a sensor fault.
Unable to control the air flow or temperature
  • Distribution motor fault(s)
  • Control module fault
Carry out the distribution motor self-test. Refer to the relevant section of the workshop manual. Check for DTCs indicating a module fault (refer to the DTC index below).
No hot air
  • Cooling system fault
  • Viscous fan locked
  • Distribution motor fault(s)
  • Control module fault
Check the coolant level, viscous fan operation, etc. Carry out the distribution motor self-test. Refer to the relevant section of the workshop manual. Check for DTCs indicating a module fault (refer to the DTC index below).

DTC index

:
  Generic scan tools may not read the codes listed, or may read only 5-digit codes. Match the 5 digits from the scan tool to the first 5 digits of the 7-digit code listed to identify the fault (the last 2 digits give extra information read by the manufacturer-approved diagnostic system).

:
  For a full list of climate control DTCs, refer to the Control Components section of the workshop manual.

DTC Description Possible causes Action
B1A5911 Sensor 5 Volt Supply
  • Ambient air temperature sensor 5 volt supply short circuit to ground
Refer to the electrical guide and check the ambient air temperature sensor circuit. Refer to the guided diagnostic routine for this code on the approved diagnostic system.
B1A6312 Right Solar Sensor
  • Right-hand solar sensor signal short circuit to 5 volts
Refer to the electrical guides and check the right-hand sunlight sensor sensor circuit. Refer to the guided diagnostic routine for this code on the approved diagnostic system.
B1A6412 Left Solar Sensor
  • Left-hand solar sensor signal short circuit to 5 volts
Refer to the electrical guides and check the left-hand sunlight sensor sensor circuit. Refer to the guided diagnostic routine for this code on the approved diagnostic system.
B1B6013 Feedback Potentiometer Circuit
  • Air intake stuck in one position
  • Feedback potentiometer circuit high resistance
Check the feedback potentiometer/air temperature mode motor circuits. Refer to the electrical guides.
B1B6711 Air Intake Servo Potentiometer Circuit
  • Recirculation motor signal short circuit to ground
Check the intake air motor circuit. Refer to the electrical guides. Refer to the guided diagnostic routine for this code on the approved diagnostic system.
B1B6715 Air Intake Servo Potentiometer Circuit
  • Recirculation motor signal high resistance
  • Recirculation motor signal short circuit to power
Check the intake air motor circuit. Refer to the electrical guides. Refer to the guided diagnostic routine for this code on the approved diagnostic system.
B1B6801 Air Intake Servo Motor
  • Recirculation motor fault
Check the intake air motor circuit. Refer to the electrical guides. Refer to the guided diagnostic routine for this code on the approved diagnostic system.
B1B7400 Foot/Defrost Damper Actuator
  • Actuator mechanical fault
  • Actuator overheating
  • Actuator circuit high resistance
  • Actuator circuit short circuit
  • Actuator power failure
Check for mechanical faults with the face/feet distribution motor (see visual inspection). Refer to the guided diagnostic routine for this code on the approved diagnostic system.
B1B7449 Foot/Defrost Damper Actuator
  • Actuator internal fault
Check the face/feet distribution motor operation. Refer to the guided diagnostic routine for this code on the approved diagnostic system.
B1B7700 Front Right Air Blend Stepper Actuator
  • Actuator mechanical fault
  • Actuator overheating
  • Actuator circuit high resistance
  • Actuator circuit short circuit
  • Actuator power failure
Check for the right-hand air temperature motor mechanical faults (see visual inspection). Refer to the guided diagnostic routine for this code on the approved diagnostic system.
B1B7749 Front Right Air Blend Stepper Actuator
  • Actuator internal fault
Refer to the guided diagnostic routine for this code on the approved diagnostic system.