| BRAKE LAMP DOES NOT ILLUMINATE |
1. Ineffective ground circuit. |
1. Test and repair open brake lamp ground circuit if required. |
| 2. Ineffective fuse. |
2. Test and replace the fuse in the BCM if required. |
| 3. Ineffective feed circuit. |
3. Test and repair open brake lamp switch output circuit or stop lamp output circuit if required. |
| 4. Ineffective switch. |
4. Test and replace brake lamp switch if required. |
| 5. Ineffective BCM inputs or outputs. |
5. Use a diagnostic scan tool to test the BCM inputs and outputs. Refer to the appropriate diagnostic information. |
| BRAKE LAMP DOES NOT EXTINGUISH |
1. Ineffective feed circuit. |
1. Test and repair shorted brake lamp switch output circuit or stop lamp output circuit if required. |
| 2. Improperly adjusted switch. |
2. Adjust the brake lamp switch if required. |
| 3. Ineffective switch. |
3. Test and replace brake lamp switch if required. |
| 4. Ineffective BCM inputs or outputs. |
4. Use a diagnostic scan tool to test the BCM inputs and outputs. Refer to the appropriate diagnostic information. |