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Pinpoint Test U: B10B5:11, B10B5:15, B10B6:11, B10B6:15

WARNING: This page is about a different car, the 2023 Ford Bronco. However, it is still accessible from the selected car via links, so may be relevant.
  1. Refer to MANUAL CLIMATE CONTROL SYSTEM for schematic and connector information.

    Normal Operation and Fault Conditions 

    The air discharge sensors supply a varying voltage to the HVAC control module based on the temperature of the air being discharged from the vent. The HVAC control module adjusts the system based on the voltage from each sensor.

    Each air discharge sensor is supplied voltage from the HVAC control module and all sensors share a common sensor ground. An open, a short to ground, a short to voltage on one or more of these circuits or a failed air discharge sensor causes the HVAC control module to set one or more Diagnostic Trouble Codes (DTCs).

    DTC Fault Trigger Conditions 

    DTC Description Fault Trigger Condition
    HVAC B10B5:11 Left Panel Air Discharge Temperature: Circuit Short To Ground Module senses erratic voltages from the air discharge temperature sensor.
    HVAC B10B5:15 Left Panel Air Discharge Temperature: Circuit Short To Battery Or Open Module senses erratic voltages from the air discharge temperature sensor.
    HVAC B10B6:11 Left Floor Air Discharge Temperature: Circuit Short To Ground Module senses erratic voltages from the air discharge temperature sensor.
    HVAC B10B6:15 Left Floor Air Discharge Temperature: Circuit Short To Battery Or Open Module senses erratic voltages from the air discharge temperature sensor.

    Possible Sources 

    • Wiring, terminals or connectors
    • Air discharge temperature sensor
    • HVAC control module

    NOTE: Use the correct probe adapter(s) when making measurements. Failure to use the correct probe adapter(s) may cause damage to the connector.

  2. U1 CHECK THE AIR DISCHARGE TEMPERATURE SENSOR OUTPUT VOLTAGE

    • Ignition OFF.

    • Disconnect the suspect air discharge temperature sensor:

      • Driver Side Footwell (Floor) Air Discharge Temperature Sensor C2436
      • Driver Side Register (Panel) Air Discharge Temperature Sensor C2438

    • Ignition ON.

    • On the HVAC controls, select PANEL mode.

    • For the Driver Side Footwell (Floor) Air Discharge Temperature Sensor, measure:
      Positive Lead Measurement / Action Negative Lead
      C2436 Pin 1
      GFD758227Courtesy of FORD MOTOR COMPANY
      		 C2436 Pin 3

    • For the Driver Side Register (Panel) Air Discharge Temperature Sensor, measure:
      Positive Lead Measurement / Action Negative Lead
      C2438 Pin 1
      GFD758227Courtesy of FORD MOTOR COMPANY
      		 C2438 Pin 3

    Are the voltages between 4.7 and 5.1 volts? 

    Yes  INSTALL a new air discharge temperature sensor. REFER to Driver Side Footwell Air Discharge Temperature Sensor . CLEAR the Diagnostic Trouble Codes (DTCs). REPEAT the self-test. If the DTC returns, GO to U6 
    No  GO to U2 

  3. U2 CHECK THE AIR DISCHARGE TEMPERATURE SENSOR CIRCUITS FOR A SHORT TO VOLTAGE

    • Ignition OFF.

    • Ignition ON.

    • For the Driver Side Footwell (Floor) Air Discharge Temperature Sensor, measure:
      Positive Lead Measurement / Action Negative Lead
      C2436 Pin 1
      GFD758227Courtesy of FORD MOTOR COMPANY
      		 Ground
      C2436 Pin 3
      GFD758227Courtesy of FORD MOTOR COMPANY
      		 Ground

    • For the Driver Side Register (Panel) Air Discharge Temperature Sensor, measure:
      Positive Lead Measurement / Action Negative Lead
      C2438 Pin 1
      GFD758227Courtesy of FORD MOTOR COMPANY
      		 Ground
      C2438 Pin 3
      GFD758227Courtesy of FORD MOTOR COMPANY
      		 Ground

    Is any voltage present? 

    Yes  REPAIR the circuit.
    No  GO to U3 

  4. U3 CHECK THE AIR DISCHARGE TEMPERATURE SENSOR CIRCUITS FOR A SHORT TO GROUND

    • Ignition OFF.

    • For the Driver Side Footwell (Floor) Air Discharge Temperature Sensor, measure:
      Positive Lead Measurement / Action Negative Lead
      C2436 Pin 1
      GFD758228Courtesy of FORD MOTOR COMPANY
      		 Ground
      C2436 Pin 3
      GFD758228Courtesy of FORD MOTOR COMPANY
      		 Ground

    • For the Driver Side Register (Panel) Air Discharge Temperature Sensor, measure:
      Positive Lead Measurement / Action Negative Lead
      C2438 Pin 1
      GFD758228Courtesy of FORD MOTOR COMPANY
      		 Ground
      C2438 Pin 3
      GFD758228Courtesy of FORD MOTOR COMPANY
      		 Ground

    Are the resistances greater than 10, 000 ohms? 

    Yes  GO to U4 
    No  REPAIR the circuit.

  5. U4 CHECK THE AIR DISCHARGE TEMPERATURE SENSOR CIRCUITS FOR AN OPEN

    • For the Driver Side Footwell (Floor) Air Discharge Temperature Sensor, measure:
      Positive Lead Measurement / Action Negative Lead
      C2436 Pin 1
      GFD758228Courtesy of FORD MOTOR COMPANY
      		 C228B Pin 4
      Positive Lead Measurement / Action Negative Lead
      C2436 Pin 3
      GFD758228Courtesy of FORD MOTOR COMPANY
      		 C228A Pin 2

    • For the Driver Side Register (Panel) Air Discharge Temperature Sensor, measure:
      Positive Lead Measurement / Action Negative Lead
      C2438 Pin 1
      GFD758228Courtesy of FORD MOTOR COMPANY
      		 C228B Pin 5
      Positive Lead Measurement / Action Negative Lead
      C2438 Pin 3
      GFD758228Courtesy of FORD MOTOR COMPANY
      		 C228A Pin 2

    Are the resistances less than 3 ohms? 

    Yes  GO to U5 
    No  REPAIR the circuit.

  6. U5 CHECK AIR DISCHARGE TEMPERATURE SENSOR CIRCUITS FOR A SHORT TO TOGETHER

    • For the Driver Side Footwell (Floor) Air Discharge Temperature Sensor, measure:
      Positive Lead Measurement / Action Negative Lead
      C2436 Pin 1
      GFD758228Courtesy of FORD MOTOR COMPANY
      		 C2436 Pin 3

    • For the Driver Side Register (Panel) Air Discharge Temperature Sensor, measure:
      Positive Lead Measurement / Action Negative Lead
      C2438 Pin 1
      GFD758228Courtesy of FORD MOTOR COMPANY
      		 C2438 Pin 3

    Are the resistances greater than 10, 000 ohms? 

    Yes  INSTALL a new air discharge temperature sensor. REFER to Driver Side Footwell Air Discharge Temperature Sensor . CLEAR all Diagnostic Trouble Codes (DTCs). CARRY OUT the HVAC control module self-test. If the DTC returns, GO to U6 
    No  REPAIR the circuit.

  7. U6 CHECK FOR CORRECT HVAC (HEATING, VENTILATION AND AIR CONDITIONING) CONTROL MODULE OPERATION

    • Ignition OFF.

    • Disconnect and inspect all HVAC control module electrical connectors (if not previously disconnected).

    • Repair:

      • corrosion (install new connector or terminal - clean module pins)
      • damaged or bent pins - install new terminals or pins
      • pushed-out pins - install new pins as necessary

    • Connect all HVAC control module electrical connectors. Make sure they seat and latch correctly.

    • Operate the system and determine if the concern is still present.

    Is the concern still present? 

    Yes  CHECK OASIS for any applicable service articles: TSB, GSB, SSM or FSA. If a service article exists for this concern, DISCONTINUE this test and FOLLOW the service article instructions. If no service articles address this concern, INSTALL a new HVAC control module. REFER to: Heating, Ventilation and Air Conditioning (HVAC) Control Module .
    No  The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. ADDRESS the root cause of any connector or pin issues.
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