Diagnostic Routine Z

Diagnostic Routine Z

Diagnostic Overview

B1A61:00, B105A:00

Refer to Wiring Diagram Set 55 for schematic and connector information Electrical Diagrams.

DTC Fault Trigger Conditions






Pinpoint Test

1. CHECK THE HVAC (Heating, Ventilation, and Air Conditioning) MODULE DTCs (Diagnostic Trouble Codes)

1. Ignition ON.

2. Using a scan tool, perform HVAC (Heating, Ventilation, and Air Conditioning) module self-test.

Is DTC (Diagnostic Trouble Code) B1A61:00 received?






2. CHECK THE HVAC MODULE OUTPUT VOLTAGE

1. Disconnect: In-vehicle Temperature Sensor.

2. Ignition ON.

3. Turn the HVAC (Heating, Ventilation, and Air Conditioning) system on.

4. Measure:





Is the voltage between 4.7 and 5.1 volts?






3. CHECK THE IN-VEHICLE TEMPERATURE SENSOR FEEDBACK CIRCUIT FOR AN OPEN

1. Ignition OFF.

2. Disconnect: HVAC (Heating, Ventilation, and Air Conditioning) Module C228B.

3. Measure:





Is the resistance less than 3 ohms?






4. CHECK THE IN-VEHICLE TEMPERATURE SENSOR FEEDBACK CIRCUIT FOR SHORT TO GROUND

1. Measure:





Is the resistance greater than 10,000 ohms?






5. CHECK THE IN-VEHICLE TEMPERATURE SENSOR FEEDBACK CIRCUIT FOR SHORT TO POWER

1. Ignition ON.

2. Measure:





Is any voltage present?






6. CHECK THE SIGNAL RETURN CIRCUIT FOR AN OPEN

1. Measure:





Is the resistance less than 3 ohms?






7. CHECK THE ASPIRATOR FAN POWER CIRCUIT FOR AN VOLTAGE

1. Disconnect: In-vehicle Temperature Sensor.

2. Ignition ON.

3. Measure:





Is the voltage greater than 11 volts?






8. CHECK THE ASPIRATOR FAN GROUND CIRCUIT FOR AN OPEN

1. Disconnect: HVAC (Heating, Ventilation, and Air Conditioning) Module C228B.

2. Measure:





Is the resistance less than 3 ohms?






9. CHECK THE ASPIRATOR FAN GROUND CIRCUIT FOR A SHORT TO GROUND

1. Measure:





Is the resistance greater than 10,000 ohms?






10. CHECK THE ASPIRATOR FAN GROUND CIRCUIT FOR A SHORT TO POWER

1. Ignition ON.

2. Measure:





Is any voltage present?






11. CHECK FOR CORRECT HVAC (Heating, Ventilation, and Air Conditioning) MODULE OPERATION

1. Ignition OFF.

2. Disconnect and inspect the HVAC (Heating, Ventilation, and Air Conditioning) module connectors.

3. Repair:

- corrosion (replace connector or terminals- clean module pins)
- damaged or bent pins- replace terminals/pins
- pushed-out pins- replace pins as necessary

4. Reconnect the HVAC (Heating, Ventilation, and Air Conditioning) module connectors. Make sure they seat and latch correctly.

5. Operate the system and verify the concern is still present.

Is the concern still present?