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Diagnostic Routine C




Diagnostic Routine C

Diagnostic Overview

C1B14:11, C1B14:12

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

Normal Operation and Fault Conditions

A 5-volt reference voltage is supplied to the sensors and actuators from the HVAC (Heating, Ventilation, and Air Conditioning) module.

DTC Fault Trigger Conditions






Pinpoint Test

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

1. Ignition ON.

2. Review the recorded DTCs (Diagnostic Trouble Codes) from the HVAC (Heating, Ventilation, and Air Conditioning) module self-test.

Is DTC (Diagnostic Trouble Code) C1B14:11 present?








2. CHECK THE REFERENCE VOLTAGE CIRCUIT FOR A SHORT TO GROUND

1. Ignition OFF.

2. Disconnect: HVAC (Heating, Ventilation, and Air Conditioning) Module C228A.

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

4. Disconnect: Auxiliary Climate Control Assembly.

5. Measure:





Is the resistance greater than 10,000 ohms?








3. CHECK THE REFERENCE VOLTAGE CIRCUIT AND THE SIGNAL RETURN CIRCUIT FOR A SHORT TOGETHER

1. Connect: Auxiliary Climate Control Assembly.

2. Measure:





Is the resistance greater than 200 ohms?








4. CHECK THE ACTUATORS

1. Measure:





2. While measuring the resistance, disconnect the components one at a time, in order. Stop disconnecting components if the measured resistance rises above 200 ohms:

- Defrost/panel/floor door actuator
- LH (Left Hand) temperature blend door actuator
- RH (Right Hand) temperature blend door actuator
- Recirculation door actuator
- In-vehicle temperature/humidity sensor
- Auxiliary mode door actuator
- Auxiliary temperature blend door actuator
- Auxiliary climate control assembly

Did the resistance rise above 200 ohms?








5. CHECK THE REFERENCE VOLTAGE CIRCUIT FOR A SHORT TO VOLTAGE

1. Ignition OFF.

2. Disconnect: HVAC (Heating, Ventilation, and Air Conditioning) Module C228A.

3. Ignition ON.

4. Measure:





Is any voltage present?








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

1. Ignition OFF.

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

3. Repair:

- corrosion (install new connector or terminals- clean module pins)
- damaged or bent pins- install new terminals/pins
- pushed-out pins- install new 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 determine if the concern is still present.

Is the concern still present?