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Home >> Lexus >> 2017 >> IS 350 Base, AWD >> Repair and Diagnosis (Single Page) >> Accessories & Equipment >> Anti-Theft Systems >> Smart Access System (For Entry) - Diagnostic Codes & Symptom Tests (1 Of 2) >> Smart Access System With Push-Button Start (For Entry Function) >> Dtc B27A1: Open In Driver Side Electrical Antenna Circuit [04/2013 - ] >> Description
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Dtc B27A1: Open In Driver Side Electrical Antenna Circuit [04/2013 - ]: Description

The Certification Ecu (Smart Key Ecu Assembly) Generates A Request Signal And Transmits The Signal To The Front Door Outside Handle Assembly (For Driver Door) (Electrical Key Antenna) At Intervals Of 0.25 Seconds. For The Front Door Outside Handle Assembly (For Driver Door) (Electrical Key Antenna) To Detect When The Electrical Key Transmitter Sub-Assembly Is Brought Close To The Vehicle, A Signal Requesting A Response From The Electrical Key Transmitter Sub-Assembly Is Transmitted Within Approximately 1 M (3.28 Ft.) Of The Driver Door At Intervals Of 0.25 Seconds. Dtc B27A1 Is Stored By The Certification Ecu (Smart Key Ecu Assembly) When An Open Circuit Is Detected Between The Certification Ecu (Smart Key Ecu Assembly) And Front Door Outside Handle Assembly (For Driver Door) (Electrical Key Antenna) (Between Terminals Clg1 And Ant1, Or Terminals Cg1B And Ant2).

Dtc No. Detection Item Dtc Detection Condition Trouble Area Note
B27A1 Open In Driver Side Electrical Antenna Circuit An Open Circuit Is Detected In The Circuit Between The Certification Ecu (Smart Key Ecu Assembly) And Front Door Outside Handle Assembly (For Driver Door) (Clg1 - Ant1, Cg1B - Ant2) (This Is Detected By The Malfunction Detection Circuit In The Certification Ecu (Smart Key Ecu Assembly)) (1 Trip Detection Logic*).
  • Certification Ecu (Smart Key Ecu Assembly)
  • Front Door Outside Handle Assembly (For Driver Door)
  • Wire Harness Or Connector
Dtc Output Confirmation Operation: 
  1. Any Time
  1. *: Only Output While A Malfunction Is Present.
Vehicle Condition And Fail-Safe Operation When Malfunction Detected

Vehicle Condition When Malfunction Detected Fail-Safe Operation When Malfunction Detected
Entry Lock/Unlock Operation Cannot Be Performed For Driver Door -
Related Data List And Active Test

Dtc Code Data List And Active Test
B27A1 Key Diagnostic Mode Can Be Used To Perform Troubleshooting