OBD Guide

B23A1

Flash To Pass / Optical Horn Switch Circuit Stuck

B23A1 is an OBD-II diagnostic trouble code meaning: Flash To Pass / Optical Horn Switch Circuit Stuck. Common causes: stuck/damaged steering column switch contacts, open/short circuit in wiring harness. Estimated repair cost: $22–89.

Severity
⚠️ Medium
Can you drive?
Limited driving only, diagnose soon
Approx. repair cost
$22–89 (est.)

Symptoms

  • Failure of the Flash To Pass function (short-term inclusion of high beams)
  • Spontaneous turning on/off of high beams
  • Check Engine Light or Headlight Warning Is On

Causes

  • Stuck/damaged steering column switch contacts
  • Open/short circuit in wiring harness
  • Oxidation or poor contact in connectors
  • Body Control Module (BCM) malfunction

How to Fix

  1. Diagnostics of the operation of the steering column switch
  2. Checking the integrity of the wiring harness from the switch to the BCM
  3. Cleaning contacts in connectors
  4. Checking BCM block parameters with a scanner
  5. Replacing a faulty switch or repairing wiring

Related codes

FAQ

What does the B23A1 code mean?

B23A1 is an OBD-II diagnostic trouble code that indicates: Flash To Pass / Optical Horn Switch Circuit Stuck

What causes a B23A1 error code?

The most common causes of B23A1 include: Stuck/damaged steering column switch contacts; Open/short circuit in wiring harness; Oxidation or poor contact in connectors; Body Control Module (BCM) malfunction.

How do I fix a B23A1 diagnostic trouble code?

To fix B23A1: Diagnostics of the operation of the steering column switch. Checking the integrity of the wiring harness from the switch to the BCM. Cleaning contacts in connectors. For a complete diagnosis, use an OBD-II scanner.

Is it safe to drive with B23A1?

Limited driving only, diagnose soon

How much does it cost to fix B23A1?

The estimated repair cost for B23A1 is $22–89. Actual cost depends on your vehicle, location, and labor rates.

See also: Russian version · NationStat