Engine-Codes - Generic - B1278

B1278 - Headlight Switch ON Position Circuit Malfunction

Repair Importance Level: 3/3
Repair Difficulty Level: 3/3  What is this?
Table of contents

B1278 Possible Causes

  • Faulty Combination Headlight Switch
  • Combination Headlight Switch harness is open or shorted
  • Combination Headlight Switch circuit poor electrical connection
  • Faulty Multiplex Integrated Control Unit (MICU)

How is the B1278 code repair?

Start by checking the "Possible Causes" listed above. Visually inspect the related wiring harness and connectors. Check for damaged components and look for broken, bent, pushed out, or corroded connector's pins.

What is the cost to diagnose the B1278 code

Labor: 1.0

The cost to diagnose the B1278 code is 1.0 hour of labor. The auto repair labor rates vary widely across the country, and even within the same city. Most auto repairs shops charge between $75 and $150 per hour.
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Possible Symptoms

  • Engine Light ON (or Service Engine Soon Warning Light)

B1278 Meaning

The Multiplex Integrated Control Unit (MICU) monitors the Headlight Switch Position. The MICU sets the OBDII code when the Headlight Switch Position is not to factory specifications.

More Information

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Information for specific makes

  • B1278 ACURA Headlight Switch ON Position Circuit Malfunction
  • B1278 HONDA Headlight Switch ON Position Circuit Malfunction

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