Brake Switch Signal

1. Check the brake lights.
Are the brake lights on without depressing the brake pedal?
YES-Inspect the brake switch.
NO-Go to step 2.
2. Depress 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 depressed.
Is there battery voltage?
YES-The brake switch signal is OK.
NO-Repair open in the wire between the ECM/PCM (A32) and the brake 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 switch and the STOP (20 A) fuse. Inspect the brake switch.
NO-Repair short in the wire between the ECM/PCM (A32) and the STOP (20 A) fuse. Replace the STOP (20 A) fuse.