Pinpoint Test F: The Charging System Warning Indicator Lamp Flickers Or Is Intermittent

WARNING: This page is about a different car, the 2005 Ford Pickup, 2005 Ford F550 Super Duty, 2005 Ford F450 Super Duty, and 2005 Ford Cab & Chassis. However, it is still accessible from the selected car via links, so may be relevant.

NOTE: 6.0L diesel generator shown, all others are similar.

F1 CHECK FOR LOOSE CONNECTIONS
- Check all the generator, battery, and power distribution connections for looseness, corrosion, loose or bent terminals, or loose eyelets.
- Are all the connections clean and tight?
- Yes : GO to F2.
- No : REPAIR as necessary. TEST the system for normal operation.
F2 CHECK THE FUSE CONNECTIONS
- Key in START position.
  With the engine running, check the CJB fuse 45 (10A) in I circuit 904 (LG/RD) for looseness by wiggling the fuse and noting the charging system warning indicator operation.
- Does the charging system warning indicator flicker?
- Yes : REPAIR the loose fuse connection(s) as necessary. TEST the system for normal operation.
- No : GO to F3.
F3 CHECK A CIRCUIT 35 (OG/LB) CONNECTIONS
- Key in OFF position.
- Connect a fused (15A) jumper wire between the generator C102a pin 3, circuit 35 (OG/LB) (back-probed), harness side and the positive battery terminal.
  
  Fig 1: Checking A Circuit 35 (OG/LB) Connections
  Courtesy of FORD MOTOR CO.
- Key in START position.
  With the engine running, note the charging system warning indicator operation.
- Does the charging system warning indicator flicker?
- Yes : If the generator has an external stator circuit 4 WH/BK), GO to F4. If the generator has an internal stator circuit, GO to F5.
- No : REPAIR the loose connection(s) in circuit 35 (OG/LB). TEST the system for normal operation.
F4 INSPECT THE S TERMINAL
- Key in OFF position.
- Check the generator S terminal C102b to make sure it is correctly mated to the generator and making good contact with the S terminal on the generator.
- Is the S terminal seated correctly?
- Yes : GO to F5.
- No : REPAIR as necessary. TEST the system for normal operation.
F5 CHECK THE GENERATOR BRUSHES
- Remove the generator from the vehicle. REFER to GENERATOR AND REGULATOR .
- Measure the resistance between the A and F terminals on the voltage regulator.
  
  Fig 2: Measuring Resistance Between A And F Terminals On Voltage Regulator
  Courtesy of FORD MOTOR CO.
- Is the resistance less than 5 ohms?
- Yes : INSTALL a new generator. REFER to GENERATOR AND REGULATOR . TEST the system for normal operation.
- No : GO to F6.
F6 CHECK FOR A GROUNDED SLIP RING
- Remove the voltage regulator. REFER to GENERATOR AND REGULATOR .
- Measure the resistance between the generator slip rings.
  
  Fig 3: Checking For Grounded Slip Ring
  Courtesy of FORD MOTOR CO.
- Is the resistance greater than 10,000 ohms?
- Yes : INSTALL a new generator. REFER to GENERATOR AND REGULATOR . TEST the system for normal operation.
- No : If the generator has an external stator circuit 4 (WH/BK), INSTALL a new regulator. REFER to GENERATOR AND REGULATOR . If the generator has an internal stator circuit, INSTALL a new generator. REFER to GENERATOR AND REGULATOR . TEST the system for normal operation.