Pinpoint Test J: The Brake Warning Indicator Is Never 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.

J1 CHECK BRAKE WARNING OPERATION
- Apply the parking brake.
- Key in ON position.
- Does the brake warning indicator illuminate?
- Yes : GO to J5.
- No : GO to J2.
J2 CHECK THE PARKING BRAKE SWITCH
- Disconnect: Parking Brake Switch C2015.
- Connect a fused (10A) jumper wire between the parking brake switch C2015-1, circuit 162 (LG/RD), harness side and ground.
  
  Fig 1: Connecting Fused (10A) Jumper Wire Between Parking Brake Switch C2015-1, Circuit 162 (LG/RD), Harness Side And Ground
  Courtesy of FORD MOTOR CO.
- Does the brake warning indicator illuminate?
- Yes : REMOVE the jumper wire. GO to J3.
- No : REMOVE the jumper wire. GO to J4.
J3 CHECK CIRCUIT 57 (BK) FOR AN OPEN
- Measure the resistance between the parking brake switch C2015-2, circuit 57 (BK), harness side and ground.
  
  Fig 2: Measuring Resistance Between Parking Brake Switch C2015-2, Circuit 57 (BK), Harness Side And Ground
  Courtesy of FORD MOTOR CO.
- Is the resistance less than 5 ohms?
- Yes : INSTALL a new parking brake switch. REFER to PARKING BRAKE & ACTUATION . TEST the system for normal operation.
- No : REPAIR the circuit. TEST the system for normal operation.
J4 CHECK CIRCUIT 162 (LG/RD) FOR AN OPEN
- Disconnect: Instrument Cluster C220b.
- Measure the resistance between the instrument cluster C220b-9, circuit 162 (LG/RD), harness side and the parking brake switch C2015-1, circuit 162 (LG/RD), harness side.
  
  Fig 3: Checking Circuit 162 (LG/RD) For An Open
  Courtesy of FORD MOTOR CO.
- Is the resistance less than 5 ohms?
- Yes : GO to J8.
- No : REPAIR the circuit. TEST the system for normal operation.
J5 CHECK THE BRAKE FLUID SWITCH
- Disconnect: Brake Fluid Level Switch C124.
- Does the brake warning indicator illuminate?
- Yes : GO to J7.
- No : GO to J6.
J6 CHECK THE BRAKE FLUID LEVEL SWITCH CIRCUITS 531 (DG/YE) AND 512 (TN/LG) FOR A SHORT
- Key in OFF position.
- Disconnect: Instrument Cluster C220b.
- Measure the resistance between the instrument cluster C220b-19, circuit 531 (DG/YE), harness side and the instrument cluster C220b-20, circuit 512 (TN/LG), harness side.
  
  Fig 4: Checking Brake Fluid Level Switch Circuits 531 (DG/YE) And 512 (TN/LG) For Short
  Courtesy of FORD MOTOR CO.
- Is the resistance greater than 10,000 ohms?
- Yes : GO to J8.
- No : REPAIR the circuits. TEST the system for normal operation.
J7 CHECK CIRCUIT 57 (BK) FOR AN OPEN
- Measure the resistance between the brake fluid level switch C124-1, circuit 57 (BK), harness side and ground.
  
  Fig 5: Measuring Resistance Between Brake Fluid Level Switch C124-1, Circuit 57 (BK), Harness Side And Ground
  Courtesy of FORD MOTOR CO.
- Is the resistance less than 5 ohms?
- Yes : INSTALL a new master cylinder. REFER to HYDRAULIC BRAKE ACTUATION . TEST the system for normal operation.
- No : REPAIR the circuit. TEST the system for normal operation.
J8 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. Concern may have been caused by a loose or corroded connector. TEST the system for normal operation.