What does it mean?
B1277 is a Body (airbags, seat belts, body electronics) fault code. It indicates: Headlight AUTO Position Circuit Malfunction .
Symptoms
- The headlights never switch on automatically at dusk or in tunnels
- The headlights come on and stay on regardless of the light level
- The AUTO position has no effect while the manual positions still work
- The cluster light indicator does not match the selected position
- The function may work intermittently, especially in damp weather
Likely causes
- Faulty AUTO position contact inside the combination light switch
- Open or shorted wiring between the AUTO position terminal and the body control module
- Corroded or loose steering column switch connector
- Water damage to the switch assembly from a windshield or cowl leak
- Harness damage under the column after clockspring, airbag, or cluster service
- Failed input circuit inside the body control module
How to fix it
- Test each light switch position in turn and confirm exactly which ones fail
- Check the AUTO position status in live data while rotating the switch through its detents
- Unplug the combination switch and measure continuity of the AUTO contact in that position
- Inspect the connector for corrosion, moisture, and spread terminals
- Test the wire between the switch and the body control module for opens and shorts
- Replace the combination light switch if the contact is bad, then verify automatic operation by covering the light sensor