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B1780ModerateBody

B1780 on 2022-2024 Lexus LX — Theft Lock / Anti-Theft System Enabled (manufacturer-specific)

1 vehicles · 1 makes

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Most Reported On

2022-2024Lexus LX

B1780 is an OBD-II diagnostic trouble code meaning “Theft Lock / Anti-Theft System Enabled (manufacturer-specific).” B1780 is a manufacturer-specific body code; on General Motors vehicles it is commonly listed as the anti-theft (Theft Lock) system being enabled, meaning the immobilizer/security function has activated and may be inhibiting normal operation. It indicates a security/anti-theft state or fault rather than a mechanical failure. Depending on the make and circumstances it can be informational or can be associated with a crank/no-start condition. Confirm the exact definition for the specific vehicle. This code is most commonly reported on 2022-2024 Lexus LX.

On This Page

  • Common Causes
  • Vehicles (1)
  • Related Codes
  • FAQ
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Common Causes

1Anti-theft system triggered or not yet relearned
2Unrecognized or unprogrammed key/transponder
3Faulty ignition lock cylinder or anti-theft sensor
4Wiring or connector fault in the security circuit
5Discharged or weak battery during start
6Faulty body control or anti-theft module

Diagnostic Tools

To diagnose B1780, you'll need an OBD-II scanner. Here are our recommendations at every price point.

Budget Pick$10–$20

ANCEL AD310 Classic OBD-II Scanner

by ANCEL

A simple, affordable code reader that reads and clears check engine codes. Great for quick diagnostics on any OBD-II vehicle (1996+).

  • Read & clear engine codes
  • View freeze frame data
  • I/M readiness status
  • No batteries or app needed
Check Price on Amazon
Best Value$90–$120

BlueDriver Pro Bluetooth Scanner

by BlueDriver

Bluetooth OBD-II scanner with a free companion app. Provides enhanced diagnostics, smog readiness, and repair reports sourced from a database of verified fixes.

  • Enhanced diagnostics (ABS, SRS, transmission)
  • Repair Reports with verified fixes
  • Smog check readiness
  • Free app (iOS & Android)
Check Price on Amazon
Advanced$180–$230

LAUNCH CRP123X OBD-II Scanner

by LAUNCH

A professional-grade handheld scanner that reads all four major systems (engine, transmission, ABS, SRS) with live data streaming and graphing.

  • Engine, transmission, ABS, SRS diagnostics
  • Live data stream & graphing
  • AutoVIN for vehicle identification
  • Free lifetime updates via Wi-Fi
Check Price on Amazon
Professional$350–$450

Autel MaxiCOM MK808S Diagnostic Tool

by Autel

Shop-level diagnostic tablet with bi-directional control, active tests, and full system coverage. Ideal for serious DIYers and small shops.

  • All-system diagnostics (25+ modules)
  • Bi-directional control & active tests
  • Oil reset, EPB, BMS, TPMS, injector coding
  • 7-inch touchscreen with Android OS
Check Price on Amazon

As an Amazon Associate, we earn from qualifying purchases. Prices are approximate and may vary.

Vehicles Affected (1)

Lexus B1780 page →
LXCritical

Front Occupant Classification / Airbag Sensor Fault Triggering SRS Warning and Airbag Recall Repairs

2022-2024$0-$2,5000 reports

Related Codes (8)

B0081First Row Center Seatbelt Load Limiter Deployment Control (Subfault)B0092Left Side Restraints Sensor 2 (Subfault)B0098Right Side Restraints Sensor 3 (Subfault)B00A0Occupant Classification System (Subfault)B0229Manufacturer-Specific Body Code (GM: Air Recirculation Door Position Feedback Circuit Actuator Range/Performance)B0408Temperature Control (Air Mix) Circuit MalfunctionB0414Manufacturer-Specific Body Code (GM: A/C Air Temperature Left Feedback Circuit Actuator Range/Performance)B0423Air Temperature Control (Passenger/Right Side) Circuit Performance

FAQ

What does B1780 mean?

B1780 stands for "Theft Lock / Anti-Theft System Enabled (manufacturer-specific)." B1780 is a manufacturer-specific body code; on General Motors vehicles it is commonly listed as the anti-theft (Theft Lock) system being enabled, meaning the immobilizer/security function has activated and may be inhibiting normal operation. It indicates a security/anti-theft state or fault rather than a mechanical failure. Depending on the make and circumstances it can be informational or can be associated with a crank/no-start condition. Confirm the exact definition for the specific vehicle.

What are the most common causes of B1780?

The most common causes of B1780 are: Anti-theft system triggered or not yet relearned, Unrecognized or unprogrammed key/transponder, Faulty ignition lock cylinder or anti-theft sensor, Wiring or connector fault in the security circuit, Discharged or weak battery during start, Faulty body control or anti-theft module. The specific cause varies by vehicle.

How much does it cost to fix B1780?

Repair costs vary widely depending on the root cause and vehicle.

Which vehicles are affected by B1780?

Au7o has documented B1780 across 1 vehicle models from 1 manufacturers: Lexus.

Content compiled with AI assistance using NHTSA complaints, TSBs, and owner reports. May contain errors. Always verify with your vehicle's service manual.

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Vehicle data and repair guidance on this site are compiled with AI assistance and may contain errors. Always verify with your service manual or a qualified mechanic.

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