| MARKER LAMP DOES NOT ILLUMINATE |
1. Ineffective or missing bulb. |
1. Test and replace bulb if required. |
| 2. Ineffective ground circuit. |
2. Test and repair open ground circuit if required. |
| 3. Ineffective feed circuit. |
3. Test and repair open feed circuit 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. |
| HEADLAMP DOES NOT EXTINGUISH |
1. Ineffective feed circuit. |
1. Test and repair shorted feed circuit if required. |
| 2. Ineffective headlamp switch. |
2. Test and replace the headlamp switch if required. |
| 3. Ineffective BCM inputs or outputs. |
3. Use a diagnostic scan tool to test the BCM inputs and outputs. Refer to the appropriate diagnostic information. |