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Pinpoint Test O: The Fog Lamps Are Inoperative

  1. O1 CHECK THE PARK LAMPS 
    • Place the headlamp switch in the PARK position.
    • Place the multifunction switch in low beam position.
    • Do the park lamps illuminate? 
    1. Yes:  Turn off the headlamp switch. GO to O2.
    2. No:  Go To PINPOINT TEST L: THE PARKING, REAR OR LICENSE LAMPS ARE INOPERATIVE .
  2. O2 CHECK THE FOG LAMP RELAYS 
    • Disconnect: Fog Lamp Relay.
    • Disconnect: Fog Lamp Interrupt Relay.
    • Check the fog lamp relay and fog lamp interrupt relay.

      Refer to COMPONENT TESTING for schematic and connector information.

    • Are the relays OK? 
    1. Yes:  GO to O3.
    2. No:  INSTALL new relay(s). TEST the system for normal operation.
  3. O3 CHECK THE CIRCUIT 12 (LG/BK) 
    • Measure the voltage between fog lamp interrupt relay connector pin 1, circuit 12 (LG/BK), harness side and ground.
      Fig 1: Checking Circuit 12 (LG/BK)
      G03242678Courtesy of FORD MOTOR CO.
    • Is the voltage greater than 0 volts? 
    1. Yes:  GO to O4.
    2. No:  REPAIR the circuit. TEST the system for normal operation.
  4. O4 CHECK CIRCUIT 275 (YE) 
    • Measure the resistance between fog lamp interrupt relay connector pin 4, circuit 275 (YE), harness side and fog lamp relay connector pin 85, circuit 275 (YE), harness side.
      Fig 2: Checking Circuit 275 (YE)
      G03242679Courtesy of FORD MOTOR CO.
    • Is the resistance less than 5 ohms? 
    1. Yes:  GO to O5.
    2. No:  REPAIR the circuit. TEST the system for normal operation.
  5. O5 CHECK CIRCUIT 477 (LB/BK) FOR OPEN 
    • Measure the voltage between fog lamp relay connector pin 30, circuit 477 (LB/BK), harness side and ground.
      Fig 3: Checking Circuit 477 (LB/BK) For Open
      G03242680Courtesy of FORD MOTOR CO.
    • Is the voltage greater than 10 volts? 
    1. Yes:  GO to O6.
    2. No:  REPAIR the circuit. TEST the system for normal operation.
  6. O6 CHECK CIRCUIT 188 (WH/BK) 
    • Disconnect: Fog Lamp Switch C240.
    • Measure the resistance between fog lamp switch C240 pin 1, circuit 188 (WH/BK), harness side and fog lamp relay connector pin 86, circuit 188 (WH/BK), harness side; and between fog lamp switch C240 pin 1, circuit 188 (WH/BK), harness side and ground.
      Fig 4: Checking Circuit 188 (WH/BK)
      G03242681Courtesy of FORD MOTOR CO.
    • Is the resistance less than 5 ohms? 
    1. Yes:  GO to O7.
    2. No:  REPAIR the circuit. TEST the system for normal operation.
  7. O7 CHECK CIRCUIT 1205 (BK) 
    • Measure the resistance between fog lamp interrupt relay connector pin 2, circuit 1205 (BK), and ground.
      Fig 5: Checking Circuit 1205 (BK)
      G03242682Courtesy of FORD MOTOR CO.
    • Is the resistance less than 5 ohms? 
    1. Yes:  GO to O8.
    2. No:  REPAIR the circuit. TEST the system for normal operation.
  8. O8 CHECK THE FOG LAMP SWITCH 
    • Measure the resistance between fog lamp switch C240 pin 1, circuit 188 (WH/BK), connector side and fog lamp switch C240 pin 2, circuit 14 (BN), connector side with the fog lamp switch on.
      Fig 6: Checking Fog Lamp Switch
      G03242683Courtesy of FORD MOTOR CO.
    • Is the resistance less then 5 ohms? 
    1. Yes:  REPAIR circuit 478 (TN/OG). TEST the system for normal operation.
    2. No:  INSTALL a new fog lamp switch. TEST the system for normal operation.
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