What causes B1277 on a Honda?

Faulty headlight switch in the AUTO position Open or short in the AUTO position circuit Poor contact in the headlight switch MICU AUTO input at fault Corroded or loose combination switch connector pins

How do I fix B1277 on a Honda?

Scan the MICU and note the AUTO position fault Test the headlight switch in the AUTO position Backprobe the AUTO signal at the MICU Check the AUTO position wiring for an open or short Replace the headlight switch if the AUTO contact tests bad Clear the code and retest

B1277 The MICU saw a fault in the headlight switch AUTO position circuit

Q: What does B1277 mean on a Honda?

B1277. The MICU saw a fault in the headlight switch AUTO position circuit. The automatic headlights may not come on or may stay on. Applies to Honda and Acura models that use this code.

Category: Body
Severity: Body Warning Light
Applies to: Honda and Acura models that use this code

What does B1277 mean on a Honda?

B1277. The MICU saw a fault in the headlight switch AUTO position circuit. The automatic headlights may not come on or may stay on. This Honda-enhanced code applies to Honda and Acura models that use this code.

Common causes of B1277

Faulty headlight switch in the AUTO position
Open or short in the AUTO position circuit
Poor contact in the headlight switch
MICU AUTO input at fault
Corroded or loose combination switch connector pins

How to fix B1277

Scan the MICU and note the AUTO position fault
Test the headlight switch in the AUTO position
Backprobe the AUTO signal at the MICU
Check the AUTO position wiring for an open or short
Replace the headlight switch if the AUTO contact tests bad
Clear the code and retest

Sources and review

Last updated 2026-10-10.