Pinpoint Test L: The Anti-Lock Brake System (ABS) Warning Indicator Is Never/Always On

WARNING: This page is about a different car, the 2005 Ford RV Cutaway, 2005 Ford Econoline, and 2005 Ford E450 Super Duty. However, it is still accessible from the selected car via links, so may be relevant.

L1 CARRY OUT THE INSTRUMENT CLUSTER WARNING LAMPS AND CHIME ACTIVE COMMAND USING THE DIAGNOSTIC TOOL
- Key in ON position.
- Enter the following diagnostic mode on the diagnostic tool: Instrument Cluster Active Command.
- Select the instrument cluster warning lamps and chime active command. Trigger the all lamps active command on and off. Observe the ABS warning indicator.
- Does the ABS warning indicator illuminate when triggered on and turn off when triggered off?
- Yes : If the ABS warning indicator is always on, GO to L2.
  If the ABS warning indicator is inoperative, GO to L3.
- No : GO to L4.
L2 CHECK CIRCUIT 603 (DG) FOR AN OPEN
- Key in OFF position.
- Disconnect: Instrument Cluster C220b.
- Disconnect: ABS Module C135.
- Measure the resistance between the instrument cluster C220b-24, circuit 603 (DG), harness side and the ABS module C135-15, circuit 603 (DG), harness side.
  
  Fig 1: Checking Circuit 603 (DG) For An Open
  Courtesy of FORD MOTOR CO.
- Is the resistance less than 5 ohms?
- Yes : REFER to ANTI-LOCK CONTROL to continue diagnosis of the ABS system.
- No : REPAIR the circuit. TEST the system for normal operation.
L3 CHECK CIRCUIT 603 (DG) FOR A SHORT TO GROUND
- Measure the resistance between the instrument cluster C220b-24, circuit 603 (DG), harness side and ground.
  
  Fig 2: Measuring Resistance Between Instrument Cluster C220b-24, Circuit 603 (DG), Harness Side And Ground
  Courtesy of FORD MOTOR CO.
- Is the resistance less than 5 ohms?
- Yes : REPAIR the circuit. TEST the system for normal operation.
- No : GO to L5.
L4 CHECK FOR CORRECT INSTRUMENT CLUSTER OPERATION
- Disconnect all the instrument cluster connectors.
- Check for:
  - Corrosion
  - Pushed-out pins
- Connect all the instrument cluster 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 instrument cluster. REFER to INSTRUMENT CLUSTER . 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. TEST the system for normal operation.
L5 CHECK FOR CORRECT ABS MODULE OPERATION
- Disconnect the ABS connector.
- Check for:
  - Corrosion
  - Pushed-out pins
- Connect the ABS module connector and make sure it seats correctly.
- Operate the system and verify the concern is still present.
- Is the concern still present?
- Yes : INSTALL a new ABS module. REFER to ANTI-LOCK CONTROL . 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. TEST the system for normal operation.