2004 Honda S2000FACTORY OEM SERVICE PROCEDURE

Brake Pedal Position Switch Signal Circuit Troubleshooting

  1. Check the brake lights.

    Are the brake lights on without pressing the brake pedal? 

    1. YES -  Inspect the brake pedal position switch adjustment (see ABS MODULATOR-CONTROL UNIT REMOVAL AND INSTALLATION ).
    2. NO -  Go to step 2.
  2. Press the brake pedal.

    Do the brake lights come on? 

    1. YES -  Go to step 3.
    2. NO -  Go to step  4.
  3. Measure voltage between ECM connector terminals A32 and B20 with the brake pedal pressed.
    Fig 1: Measuring Voltage Between ECM Connector Terminals A32 And B20 With Brake Pedal Pressed
    G03692748Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there battery voltage? 

    1. YES -  The brake pedal position switch signal is OK.
    2. NO -  Repair open in the wire between the ECM (A32) and the brake pedal position switch.
  4. Inspect the STOP (2000-2001 models: 10 A, 2002-2005 models: 15 A) fuse in the under-hood fuse/relay box.

    Is the fuse OK? 

    1. YES -  Repair open in the wire between the brake pedal position switch and the STOP (2000-2001 models: 10 A, 2002-2005 models: 15 A) fuse. Inspect the brake pedal position switch (see BRAKE PEDAL POSITION SWITCH TEST ).
    2. NO -  Repair short in the wire between the ECM (A32) and the STOP (2000-2001 models: 10 A, 2002-2005 models: 15 A) fuse. Replace the STOP (2000-2001 models: 10 A, 2002-2005 models: 15 A) fuse.
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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • • You smell fuel, burning insulation, or see smoke.
  • • Brakes feel soft, pull hard to one side, or make grinding noises.
  • • The engine overheats, stalls repeatedly, or misfires under load.
  • • You are missing required tools, torque specs, or safe lifting equipment.
  • • You are not confident in the next step or safety outcome.