OBD Guide

B1A25

Invalid Key

B1A25 is an OBD-II diagnostic trouble code meaning: Invalid Key. Common causes: faulty chip in the key, problems with the immobilizer antenna. Estimated repair cost: $11–167.

Severity
⚠️ Medium
Can you drive?
Yes, but get it checked soon
Approx. repair cost
$11–167 (est.)

Symptoms

  • The car won't start
  • The immobilizer indicator is flashing
  • Message on the dashboard about an unrecognized key

Causes

  • Faulty chip in the key
  • Problems with the immobilizer antenna
  • Immobilizer module malfunction
  • Dead key battery or interference from electronic devices

How to Fix

  1. Check the battery in the key
  2. Try to start the car with a spare key
  3. Check the immobilizer antenna for damage
  4. Have the immobilizer diagnosed by a specialist

Related codes

FAQ

What does the B1A25 code mean?

B1A25 is an OBD-II diagnostic trouble code that indicates: Invalid Key

What causes a B1A25 error code?

The most common causes of B1A25 include: Faulty chip in the key; Problems with the immobilizer antenna; Immobilizer module malfunction; Dead key battery or interference from electronic devices.

How do I fix a B1A25 diagnostic trouble code?

To fix B1A25: Check the battery in the key. Try to start the car with a spare key. Check the immobilizer antenna for damage. For a complete diagnosis, use an OBD-II scanner.

Is it safe to drive with B1A25?

Yes, but get it checked soon

How much does it cost to fix B1A25?

The estimated repair cost for B1A25 is $11–167. Actual cost depends on your vehicle, location, and labor rates.

See also: Russian version · NationStat