Pinpoint Test F: The Heated Rear Window Will Not Shut Off Automatically

2005 Ford Crown Victoria Special EditionSECTION Pinpoint Test F: The Heated Rear Window Will Not Shut Off Automatically
  1. F1 CHECK THE HEATED REAR WINDOW RELAY INPUT FOR A SHORT TO GROUND 
    • Key in OFF position.
    • Disconnect: Heated Rear Window Relay.
    • Measure the resistance between the heated rear window relay pin 2, circuit 688 (GY/LB), harness side and ground.
      Fig 1: Checking Heated Rear Window Relay Input For A Short To Ground
      G03880517Courtesy of FORD MOTOR CO.
    • Is the resistance greater than 10,000 ohms? 
    • Yes  : GO to  F3.
    • No  : GO to  F2.
  2. F2 CHECK CIRCUIT 688 (GY/LB) FOR A SHORT TO GROUND 
    • Disconnect: Lighting Control Module (LCM) C2145b.
    • Measure the resistance between the heated rear window relay connector pin 2, circuit 688 (GY/LB), harness side and ground.
      Fig 2: Checking Circuit 688 (GY/LB) For A Short To Ground
      G03880517Courtesy of FORD MOTOR CO.
    • Is the resistance greater than 10,000 ohms? 
    • Yes  : INSTALL a new LCM. REFER to MULTIFUNCTION ELECTRONIC MODULES . TEST the system for normal operation.
    • No  : REPAIR the circuit. TEST the system for normal operation.
  3. F3 CHECK CIRCUIT 186 (BN/LB) FOR A SHORT TO VOLTAGE 
    • Key in ON position.
    • Measure the voltage between the heated rear window relay pin 5, circuit 186 (BN/LB), harness side and ground.
      Fig 3: Checking Circuit 186 (BN/LB) For A Short To Voltage
      G03880519Courtesy of FORD MOTOR CO.
    • Is voltage present? 
    • Yes  : REPAIR the circuit. TEST the system for normal operation.
    • No  : INSTALL a new heated rear window relay. TEST the system for normal operation.
RENDER: 1.0x

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