OBD Guide

B3948

Left Front Turn Signal Circuit

B3948 is an OBD-II diagnostic trouble code meaning: Left Front Turn Signal Circuit. Common causes: burnt out turn signal lamp, broken or damaged wires. Estimated repair cost: $6–33.

Severity
⚠️ Medium
Can you drive?
Limited driving only, diagnose soon
Approx. repair cost
$6–33 (est.)

Symptoms

  • Left front turn signal does not work
  • Turn signals flash faster than usual
  • Error message on the dashboard

Causes

  • Burnt out turn signal lamp
  • Broken or damaged wires
  • Poor contact in connectors
  • Turn signal relay malfunction
  • Wiring harness problem

How to Fix

  1. Check the condition of the left front turn signal lamp
  2. Inspect wires and connectors for damage
  3. Check turn signal relay
  4. Test the wiring harness for continuity
  5. Replace faulty components

Related codes

Error B3948 by Vehicle Brand

FAQ

What does the B3948 code mean?

B3948 is an OBD-II diagnostic trouble code that indicates: Left Front Turn Signal Circuit

What causes a B3948 error code?

The most common causes of B3948 include: Burnt out turn signal lamp; Broken or damaged wires; Poor contact in connectors; Turn signal relay malfunction.

How do I fix a B3948 diagnostic trouble code?

To fix B3948: Check the condition of the left front turn signal lamp. Inspect wires and connectors for damage. Check turn signal relay. For a complete diagnosis, use an OBD-II scanner.

Is it safe to drive with B3948?

Limited driving only, diagnose soon

How much does it cost to fix B3948?

The estimated repair cost for B3948 is $6–33. Actual cost depends on your vehicle, location, and labor rates.

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