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OBD-II Code Lexus

B2791 — Lexus — Key Unlock Warning Switch Malfunction (Immobilizer System)

The immobilizer system detects a malfunction in the key unlock warning switch circuit.

Brand Lexus
System Electrical System
Severity Low
Safe to drive? Yes, with caution
Advanced scanner Not necessarily

What does code B2791 mean on Lexus vehicles?

The immobilizer system detects a malfunction in the key unlock warning switch circuit.

Common symptoms

  • Incorrect alarm activation
  • warning messages

Possible causes

  • Faulty key warning switch
  • wiring issue

Initial recommendation

Inspect key warning switch and related wiring.

Safety notice

This information is for guidance only. Brand-specific codes may vary by model, year, engine, transmission and vehicle configuration. It does not replace a physical inspection or diagnosis by a qualified mechanic. If the vehicle is unsafe to operate, avoid driving it and seek professional inspection.

Analyze this code with MecaOBD

Use the app to combine Lexus code B2791 with your vehicle's actual symptoms for more complete diagnostic guidance.

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