OBD Guide

B2126

Detention Switch

B2126 is an OBD-II diagnostic trouble code meaning: Detention Switch. Common causes: faulty lock switch, open or short circuit in wiring harness. Estimated repair cost: $56–167.

Severity
⚠️ Medium
Can you drive?
Do not drive — repair immediately
Approx. repair cost
$56–167 (est.)

Symptoms

  • The security system malfunction indicator is on
  • Airbags may not deploy in an emergency situation
  • The passive safety system can be partially or completely disabled

Causes

  • Faulty lock switch
  • Open or short circuit in wiring harness
  • Poor contact in the switch connector
  • Problems with the security control module

How to Fix

  1. Check the condition of the lock switch
  2. Inspect the wiring harness and connectors for damage
  3. Check the resistance of the switch with a multimeter
  4. If necessary, replace the lock switch
  5. Reset the error and check the system

Related codes

FAQ

What does the B2126 code mean?

B2126 is an OBD-II diagnostic trouble code that indicates: Detention Switch

What causes a B2126 error code?

The most common causes of B2126 include: Faulty lock switch; Open or short circuit in wiring harness; Poor contact in the switch connector; Problems with the security control module.

How do I fix a B2126 diagnostic trouble code?

To fix B2126: Check the condition of the lock switch. Inspect the wiring harness and connectors for damage. Check the resistance of the switch with a multimeter. For a complete diagnosis, use an OBD-II scanner.

Is it safe to drive with B2126?

Do not drive — repair immediately

How much does it cost to fix B2126?

The estimated repair cost for B2126 is $56–167. Actual cost depends on your vehicle, location, and labor rates.

See also: Russian version · NationStat