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B1602CriticalBody

B1602 on 2007-2017 Lexus LS (LS460, LS460L, LS600h, LS600hL) — PATS Received Invalid Format of Key-Code From Ignition Key Transponder

1 vehicles · 1 makes · $400-$1,500 repair

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Most Reported On

2007-2017Lexus LSLS460 +3

B1602 is an OBD-II diagnostic trouble code meaning “PATS Received Invalid Format of Key-Code From Ignition Key Transponder.” This is a Ford-family body code from the Passive Anti-Theft System (PATS), the immobilizer that verifies your key before allowing the engine to start. The module read the transponder chip in the key but received a code in an invalid or unrecognized format, so it could not confirm the key is authorized. The result is often a no-start or stall condition with the security/theft light illuminated. It usually points to a key, transponder, or anti-theft antenna problem rather than an engine fault. This code is most commonly reported on 2007-2017 Lexus LS (LS460, LS460L, LS600h, LS600hL), with repair costs ranging from $400 to $1,500.

On This Page

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

1Damaged, demagnetized, or non-programmed (non-PATS) key transponder
2Unprogrammed aftermarket or duplicate key being used
3Faulty or misaligned transceiver antenna ring around ignition lock
4Interference from other transponders or metal objects on the key ring
5Wiring or connector fault between the antenna and module
6Weak key fob or vehicle battery affecting the read
7Faulty PATS/anti-theft control module

Typical Repair Cost

$400 - $1,500

Based on 1 documented vehicle-specific issues. Actual cost depends on root cause and vehicle.

Diagnostic Tools

To diagnose B1602, 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+).

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  • I/M readiness status
  • No batteries or app needed
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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)
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  • Smog check readiness
  • Free app (iOS & Android)
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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
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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.

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Vehicles Affected (1)

Lexus B1602 page →
LSModerate

Self-Leveling Headlight System Failure

2007-2017$400-$1,5001,600 reports

Related Codes (8)

B1601PATS Received Incorrect Key-Code From TransponderB1609Illuminated Entry Input Short Circuit to Battery01367Central Locking Pump Run Time Exceeded (Likely Leak)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)

FAQ

What does B1602 mean?

B1602 stands for "PATS Received Invalid Format of Key-Code From Ignition Key Transponder." This is a Ford-family body code from the Passive Anti-Theft System (PATS), the immobilizer that verifies your key before allowing the engine to start. The module read the transponder chip in the key but received a code in an invalid or unrecognized format, so it could not confirm the key is authorized. The result is often a no-start or stall condition with the security/theft light illuminated. It usually points to a key, transponder, or anti-theft antenna problem rather than an engine fault.

What are the most common causes of B1602?

The most common causes of B1602 are: Damaged, demagnetized, or non-programmed (non-PATS) key transponder, Unprogrammed aftermarket or duplicate key being used, Faulty or misaligned transceiver antenna ring around ignition lock, Interference from other transponders or metal objects on the key ring, Wiring or connector fault between the antenna and module, Weak key fob or vehicle battery affecting the read, Faulty PATS/anti-theft control module. The specific cause varies by vehicle.

How much does it cost to fix B1602?

Repair costs for B1602 range from $400 to $1,500, depending on the vehicle and root cause.

Which vehicles are affected by B1602?

Au7o has documented B1602 across 1 vehicle models from 1 manufacturers: Lexus.

Get notified about B1602 fixes
We add new causes, fixes and affected vehicles for B1602 regularly — drop your email and we'll keep you posted. You can also diagnose your own car free.

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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