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Home >> Ford >> 2018 >> Taurus Limited, FWD, Gas >> Repair and Diagnosis >> External Pages >> Different car >> Section 32 (Climate Control System - General Information (2 Of 2)) >> Diagnosis And Testing >> Climate Control System - Vehicles With: Electronic Automatic Temperature Control (EATC) >> Pinpoint Tests >> Pinpoint Test K : The Blower Motor Is Inoperative

Pinpoint Test K : The Blower Motor Is Inoperative

WARNING: This page is about a different car, the 2018 Ford EcoSport. However, it is still accessible from the selected car via links, so may be relevant.
  1. Automatic Climate Control System for schematic and connector information.

    Normal Operation and Fault Conditions 

    Air Handling, REFER to: Climate Control System - Vehicles With: Electronic Automatic Temperature Control (EATC) - System Operation and Component Description .

    DTC Fault Trigger Conditions 

    DTC Description Fault Trigger Condition
    HVAC B10AF:11 Blower Fan Relay: Circuit Short To Ground This DTC sets when the HVAC control module senses no voltage change on the blower motor relay coil control circuit when the module attempts to engage the relay, indicating a short directly to ground. The blower motor is inoperative.
    HVAC B10AF:15 Blower Fan Relay: Circuit Short To Battery Or Open This DTC sets when the HVAC control module senses no ground on the blower motor relay coil control circuit when the module attempts to engage the relay, indicating an open circuit or a short directly to voltage. The blower motor is inoperative when the relay control circuit is open. The blower motor is always on when the relay control circuit is shorted to voltage.
    HVAC B10B9:12 Blower Control: Circuit Short To Battery This DTC sets when the HVAC control module senses excessive voltage on the blower motor speed control PWM circuit, indicating a short directly to voltage. The blower motor is inoperative.
    HVAC B10B9:14 Blower Control: Circuit Short To Ground Or Open This DTC sets when the HVAC control module senses no voltage on the blower motor speed control PWM circuit, indicating an open or a short directly to ground. The blower motor is inoperative.

    Possible Sources 

    • Wiring, terminals or connectors
    • Blower motor relay
    • Blower motor
    • Blower motor speed control
    • HVAC control module

    Visual Inspection and Pre-checks 

    • Inspect BJB fuse 6 (40A).

  2. NOTE: Use the correct probe adapter(s) when making measurements. Failure to. Use the correct probe adapter(s) may damage the connector.
  3. K1 CHECK THE BLOWER MOTOR RELAY FUNCTIONALITY

    • Ignition OFF.

    • Disconnect Blower motor relay.

    Did the relay pass the component test? 

    Yes  GO to  K2
    No  INSTALL a new blower motor relay.
  4. K2 CHECK THE BLOWER MOTOR RELAY COIL GROUND CIRCUIT FOR AN OPEN

    • Measure:
      Positive Lead Measurement / Action Negative Lead
      Blower motor relay socket 2
      GFD328095Courtesy of FORD MOTOR COMPANY
      Ground

    Is the resistance less than 3 ohms? 

    Yes  GO to  K3
    No  REPAIR the circuit.
  5. K3 CHECK THE BLOWER MOTOR RELAY SWITCH CONTACT SUPPLY VOLTAGE

    • Measure:
      Positive Lead Measurement / Action Negative Lead
      Blower motor relay socket 3
      GFD328094Courtesy of FORD MOTOR COMPANY
      Ground

    Is the voltage greater than 11 volts? 

    Yes  GO to  K4
    No  VERIFY BJB fuse 6 (40A) is OK. If OK, REPAIR the circuit. If not OK, REFER to OEM Electrical Wiring Diagram Introduction to identify the possible causes of the circuit short.
  6. K4 CHECK THE BLOWER MOTOR RELAY COIL CONTROL CIRCUIT FOR A SHORT TO GROUND

    • Disconnect HVAC control module C294A.

    • Measure:
      Positive Lead Measurement / Action Negative Lead
      Blower motor relay socket 1
      GFD328095Courtesy of FORD MOTOR COMPANY
      Ground

    Is the resistance greater than 10, 000 ohms? 

    Yes  GO to  K5
    No  REPAIR the circuit.
  7. K5 CHECK THE BLOWER MOTOR RELAY COIL CONTROL CIRCUIT FOR AN OPEN

    • Measure:
      Positive Lead Measurement / Action Negative Lead
      Blower motor relay socket 1
      GFD328095Courtesy of FORD MOTOR COMPANY
      Refer to C294A-11

    Is the resistance less than 3 ohms? 

    Yes  GO to  K6
    No  REPAIR the circuit.
  8. K6 CHECK THE BLOWER MOTOR SPEED CONTROL VOLTAGE CIRCUIT FOR AN OPEN

    • Disconnect Blower motor speed control C297A.

    • Measure:
      Positive Lead Measurement / Action Negative Lead
      Blower motor relay socket 5
      GFD328095Courtesy of FORD MOTOR COMPANY
      Refer to C297A-4

    Is the resistance less than 3 ohms? 

    Yes  GO to  K7
    No  REPAIR the circuit.
  9. K7 CHECK THE BLOWER MOTOR SPEED CONTROL GROUND CIRCUIT FOR AN OPEN

    • Measure:
      Positive Lead Measurement / Action Negative Lead
      Refer to C297A-2
      GFD328095Courtesy of FORD MOTOR COMPANY
      Ground

    Is the resistance less than 3 ohms? 

    Yes  GO to  K8
    No  REPAIR the circuit.
  10. K8 CHECK THE BLOWER MOTOR SPEED CONTROL PWM (PULSE WIDTH MODULATION) CIRCUIT FOR A SHORT TO VOLTAGE

    • Ignition ON.

    • Measure:
      Positive Lead Measurement / Action Negative Lead
      Refer to C297A-3
      GFD328094Courtesy of FORD MOTOR COMPANY
      Ground

    Is any voltage present? 

    Yes  REPAIR the circuit.
    No  GO to  K9
  11. K9 CHECK THE BLOWER MOTOR SPEED CONTROL PWM (PULSE WIDTH MODULATION) CIRCUIT FOR A SHORT TO GROUND

    • Ignition OFF.

    • Measure:
      Positive Lead Measurement / Action Negative Lead
      Refer to C297A-3
      GFD328095Courtesy of FORD MOTOR COMPANY
      Ground

    Is the resistance greater than 10, 000 ohms? 

    Yes  GO to  K10
    No  REPAIR the circuit.
  12. K10 CHECK THE BLOWER MOTOR SPEED CONTROL PWM (PULSE WIDTH MODULATION) CIRCUIT FOR AN OPEN

    • Measure:
      Positive Lead Measurement / Action Negative Lead
      Refer to C297A-3
      GFD328095Courtesy of FORD MOTOR COMPANY
      Refer to C294A-23

    Is the resistance less than 3 ohms? 

    Yes  GO to  K11
    No  REPAIR the circuit.
  13. K11 CHECK THE OUTPUTS TO THE BLOWER MOTOR

    • Disconnect Blower motor C2004.

    • Connect Blower motor relay.

    • Connect Blower motor speed control C297A.

    • Connect HVAC control module C294A.

    • Ignition ON.

    • Select PANEL on the HVAC controls.

    • Select the highest blower motor setting.

    • Measure:
      Positive Lead Measurement / Action Negative Lead
      Refer to C2004-1
      GFD328094Courtesy of FORD MOTOR COMPANY
      Refer to C2004-2

    Is the voltage greater than 11 volts? 

    Yes  INSTALL a new blower motor. REFER to: Blower Motor .
    No  GO to  K12
  14. K12 CHECK THE CIRCUITS TO THE BLOWER MOTOR FOR AN OPEN

    • Ignition OFF.

    • Disconnect Blower motor speed control C297B.

    • Measure:
      Positive Lead Measurement / Action Negative Lead
      Refer to C297B-1
      GFD328095Courtesy of FORD MOTOR COMPANY
      Refer to C2004-1
      Refer to C297B-2
      GFD328095Courtesy of FORD MOTOR COMPANY
      Refer to C2004-2

    Are the resistances less than 3 ohms? 

    Yes  GO to  K13
    No  REPAIR the circuit in question.
  15. K13 CHECK THE BLOWER MOTOR CIRCUITS FOR A SHORT TOGETHER

    • Measure:
      Positive Lead Measurement / Action Negative Lead
      Refer to C297B-1
      GFD328095Courtesy of FORD MOTOR COMPANY
      Refer to C297B-2

    Is the resistance greater than 10, 000 ohms? 

    Yes  INSTALL a new blower motor speed control. REFER to: Blower Motor Speed Control . TEST the system for normal operation. If the concern is still present, GO to  K14
    No  REPAIR the circuits.
  16. K14 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 Technical Service Bulletins (TSBs). If a TSB exists for this concern, DISCONTINUE this test and FOLLOW the TSB instructions. If no Technical Service Bulletins (TSBs) 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.