Pinpoint Test W: The Fog Lamp On Indicator Is Inoperative: Testing

WARNING: This page is about a different car, the 2005 Mercury Montego, 2005 Ford Freestyle, and 2005 Ford Five Hundred. However, it is still accessible from the selected car via links, so may be relevant.

W1 CHECK CIRCUIT 1407 (LB/OG) FOR AN OPEN
- Key in OFF position.
- Disconnect: SJB C2280d.
- Disconnect: Headlamp Switch C205.
- Measure the resistance between the SJB C2280d-3, circuit 1407 (LB/OG), harness side and the headlamp switch C205-3, circuit 1407 (LB/OG), harness side.
  
  Fig 1: Measuring Resistance Between SJB C2280D-3, Circuit 1407 (LB/OG), Harness Side And Headlamp Switch C205-3, Circuit 1407 (LB/OG)
  Courtesy of FORD MOTOR CO.
- Is the resistance less than 5 ohms?
- Yes : GO to W2.
- No : REPAIR the circuit. TEST the system for normal operation.
W2 CHECK THE HEADLAMP SWITCH
- Connect: Headlamp Switch C205.
- Connect a fused (5A) jumper wire between the SJB C2280d-3, circuit 1406 (YE/LG) harness side and the positive battery terminal.
  
  Fig 2: Connecting Fused (5A) Jumper Wire Between SJB C2280D-3, Circuit 1406 (YE/LG) Harness Side And Positive Battery Terminal
  Courtesy of FORD MOTOR CO.
- Does the fog lamp indicator illuminate?
- Yes : GO to W3.
- No : INSTALL a new headlamp switch. TEST the system for normal operation.
W3 CHECK FOR CORRECT SJB OPERATION
- Disconnect all the SJB connectors.
- Check for:
  - corrosion
  - pushed-out pins
- Connect all the SJB 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 SJB. REFER to MULTIFUNCTION ELECTRONIC MODULES . TEST the system for normal operation.
- No : The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. CLEAR the DTCs. REPEAT the self-test.