LEMON Manuals: Even more car manuals for everyone
Home >> Ford >> 2009 >> Flex Limited, FWD >> Repair and Diagnosis >> External Pages >> Different car >> Section 2016 (Windows And Glass - Glass, Frames And Mechanisms) >> Diagnosis And Testing >> Glass, Frames and Mechanisms >> Pinpoint Tests >> Pinpoint Test J: The Defrost System is Inoperative >> Pinpoint Test J: The Defrost System Is Inoperative

Pinpoint Test J: The Defrost System Is Inoperative

WARNING: This page is about a different car, the 2010 Lincoln MKX and 2010 Ford Edge. However, it is still accessible from the selected car via links, so may be relevant.
NOTE: Use the correct probe adapter(s) from the Flex Probe Kit when making measurements. Failure to use the correct probe adapter(s) may damage the connector.
  1. J1 CHECK CIRCUIT CRD06 (BN/YE) FOR POWER 
    • Disconnect: Rear Window Defrost Grid C402A.
    • Start the engine.
    • Turn the rear window defrost switch on.
    • Measure the voltage between rear window defrost grid C402A-1, circuit CRD06 (BN/YE), harness side and ground.
      Fig 1: Measuring Voltage Between Rear Window Defrost Grid C402A-1 And Ground
      G06070954Courtesy of FORD MOTOR CO.
    • Is the voltage greater than 10 volts? 
    • Yes:  GO to J2  .
    • No:  VERIFY BJB  fuse 39 (40A) is OK. If OK, GO to  J3.

      If not OK, REFER to the SYSTEM WIRING DIAGRAMS for Edge or SYSTEM WIRING DIAGRAMS for MKX to identify the possible causes of the circuit short. REPAIR the circuit. TEST the system for normal operation.

  2. J2 CHECK CIRCUIT GD149 (BK/GY) FOR AN OPEN 
    • Ignition OFF.
    • Disconnect: Rear Window Defrost Grid C402B.
    • Measure the resistance between rear window defrost grid C402B-1, circuit GD149 (BK/GY), harness side and ground.
      Fig 2: Measuring Resistance Between Rear Window Defrost Grid C402B-1 And Ground
      G06070955Courtesy of FORD MOTOR CO.
    • Is the resistance less than 5 ohms? 
    • Yes:  CARRY OUT the Grid Wire Test. REPAIR the rear window defrost grid or INSTALL a new liftgate glass. REFER to WINDOW GRID WIRE REPAIR . TEST the system for normal operation.
    • No:  REPAIR the circuit. TEST the system for normal operation.
  3. J3 CHECK THE VOLTAGE SUPPLY TO THE REAR WINDOW DEFROST RELAY 
    • Ignition OFF.
    • Disconnect: Rear Window Defrost Relay.
    • Ignition ON.
    • Measure the voltage between rear window defrost relay socket pin 85, circuit CBP45 (YE) and ground; and between rear window defrost relay socket pin 30, circuit SDC02 (RD) and ground.
      Fig 3: Measuring Voltage Between Rear Window Defrost Relay Socket Pin 85 And Ground
      G06504600Courtesy of FORD MOTOR CO.
    • Is the voltage greater than 10 volts? 
    • Yes:  GO to J4  .
    • No:  VERIFY SJB  fuse 45 (5A) is OK. If OK, REPAIR the circuit. TEST the system for normal operation.

      If not OK, REFER to the SYSTEM WIRING DIAGRAMS for Edge or SYSTEM WIRING DIAGRAMS for MKX to identify the possible causes of the circuit short. REPAIR the circuit. TEST the system for normal operation.

  4. J4 CHECK THE HVAC MODULE 
    NOTE: The following step uses a test light to simulate normal circuit loads. Use only the test light recommended in the Special Tools table at the beginning of this section. To avoid connector terminal damage, use the Flex Probe Kit for the test light probe connection to the vehicle. Do not use the test light probe directly on any connector.
    • Start the engine.
    • Activate the rear window defrost switch.
    • Connect a 12-volt incandescent test light between rear window defrost relay socket pin 86, circuit CH122 (WH/OG) and rear window defrost relay socket pin 85, circuit CBP45 (YE).
      Fig 4: Connecting 12-Volt Incandescent Test Light Between Rear Window Defrost Relay Socket Pin 86 And Pin 85
      G06504601Courtesy of FORD MOTOR CO.
    • Does the test light illuminate? 
    • Yes:  GO to J5  .
    • No:  GO to  J6.
  5. J5 CHECK THE REAR WINDOW DEFROST RELAY 
    • Ignition OFF.
    • Carry out the rear window defrost relay component test.

      Refer to COMPONENT TESTING for component testing.

    • Did the rear window defrost relay pass the component test? 
    • Yes:  REPAIR open in circuit CRD06 (BN/YE). TEST the system for normal operation.
    • No:  INSTALL a new rear window defrost relay. TEST the system for normal operation.
  6. J6 CHECK CIRCUIT CH122 (WH/OG) FOR AN OPEN 
    • Ignition OFF.
    • Disconnect: HVAC Module - Electronic Automatic Temperature Control (EATC) C228B or HVAC Module - EMTC  C2357A.
    • Measure the resistance between rear window defrost relay socket pin 86, circuit CH122 (WH/OG), and HVAC module - EATC  C228B-23, circuit CH122 (WH/OG), harness side; or HVAC module - EMTC  C2357A-3, circuit CH122 (WH/OG), harness side.
      Fig 5: Measuring Resistance Between Rear Window Defrost Relay Socket Pin 86 And HVAC Module - EATC C228B-23
      G06504602Courtesy of FORD MOTOR CO.
    • Is the resistance less than 5 ohms? 
    • Yes:  GO to J7  .
    • No:  REPAIR the circuit. TEST the system for normal operation.
  7. J7 CHECK FOR CORRECT HVAC MODULE OPERATION 
    • Disconnect all HVAC module electrical connectors.
    • Check for:
      • corrosion.
      • pushed-out pins.
    • Connect all HVAC module electrical connectors and make sure they seat correctly.
    • Operate the system and verify the concern is still present.
    • Is the concern still present? 
    • Yes:  INSTALL a new HVAC module. TEST the system for normal operation.
    • No:  The system is operating correctly at this time. Concern may have been caused by a loose or corroded connector. TEST the system for normal operation.
scientia non olet · About LEMON Manuals