B2791 – Lexus DTC

Lexus DTC B2791 – Key Unlock Warning Switch Malfunction (Immobilizer System)

DTC B2791 meaning on Lexus

DTC B2791 for Lexus refers to the Key Unlock Warning Switch Malfunction within the Immobilizer System. This diagnostic trouble code indicates an issue with the key unlock warning switch, which is a component of the vehicle’s immobilizer system.

Lexus DTC B2791 symptoms

Symptoms of DTC B2791 on a Lexus may include:

  • Warning light on the dashboard
  • Immobilizer system not functioning properly
  • Difficulty starting the vehicle

Lexus DTC B2791 causes

Common causes of DTC B2791 on a Lexus include:

  • Key unlock warning switch malfunction
  • Wiring or connection issues
  • Faulty immobilizer system components

Lexus DTC B2791 seriousness

The seriousness of DTC B2791 on a Lexus depends on the extent of the malfunction. Ignoring this issue may lead to potential starting problems or immobilization of the vehicle.

How to diagnose DTC B2791 on Lexus

To diagnose DTC B2791 on a Lexus, follow these steps:

  1. Use a diagnostic scanner to retrieve the trouble codes.
  2. Inspect the key unlock warning switch for any visible damage.
  3. Check the wiring and connections related to the immobilizer system.

How to fix DTC B2791 on Lexus

To fix DTC B2791 on a Lexus, you can:

  1. Replace the key unlock warning switch if faulty.
  2. Repair any damaged wiring or connections.
  3. Reset the immobilizer system.

How to erase DTC B2791 on Lexus

To erase DTC B2791 on a Lexus:

  1. Use a diagnostic scanner to clear the trouble codes.
  2. Ensure the issue has been resolved before clearing the code.

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