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Brake Pedal Position Switch Signal Circuit Troubleshooting

Brake Pedal Position Switch Signal Circuit Troubleshooting

1. Check the brake lights.

Are the brake lights on without pressing the brake pedal?

YES - Inspect the brake pedal position switch.

NO - Go to step 2.

2. Press the brake pedal.

Do the brake lights come on?

YES - Go to step 3.

NO - Go to step 4.




3. Measure voltage between ECM/PCM connector terminals A32 and B20 with the brake pedal pressed.

Is there battery voltage?

YES - The brake pedal position switch signal is OK.

NO - Repair open in the wire between the ECM/PCM (A32) and the brake pedal position switch.

4. Inspect the STOP (20 A) fuse in the under-hood fuse/relay box.

Is the fuse OK?

YES - Repair open in the wire between the brake pedal position switch and the STOP (20 A) fuse. Inspect the brake pedal position switch.

NO - Repair short in the wire between the ECM/PCM (A32) and the STOP (20 A) fuse. Replace the STOP (20 A) fuse.