DTC B27A8: Open in Outside Luggage Compartment Electrical Key Antenna Circuit [06/2018 - ]: Procedure
WARNING: This page does not describe the selected car, but rather 6 other vehicles, including the 2024 Lexus ES 300h, 2023 Lexus ES 300h, 2022 Lexus ES 300h, 2021 Lexus ES 300h, and 2020 Lexus ES 300h. However, it is still accessible from the selected car via links, so may be relevant.
- CHECK CONNECTOR CONNECTION
- Check that the connectors are properly connected to the certification ECU (smart key ECU assembly) and electrical key antenna (outside luggage compartment).
OK
Connectors are properly connected.
Result
Proceed to OK NG
Result:
NG
CONNECT CONNECTORS PROPERLY
Result:
OK
See step 2
- Check that the connectors are properly connected to the certification ECU (smart key ECU assembly) and electrical key antenna (outside luggage compartment).
- CHECK HARNESS AND CONNECTOR (CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) - ELECTRICAL KEY ANTENNA (OUTSIDE LUGGAGE COMPARTMENT))
- Disconnect the N9 certification ECU (smart key ECU assembly) connector.
- Disconnect the R2 electrical key antenna (outside luggage compartment) connector.
- Measure the resistance according to the value(s) in the table below.
Standard Resistance
Tester Connection Condition Specified Condition N9-13 (CLG8) - R2-2 (ANTE8) Always Below 1 Ω N9-12 (CG8B) - R2-1 (CLGB) Always Below 1 Ω - Reconnect the N9 certification ECU (smart key ECU assembly) connector.
Result
Proceed to OK NG
Result:
NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
Result:
OK
See step 3
- CHECK CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) (OUTPUT TO ELECTRICAL KEY ANTENNA (OUTSIDE LUGGAGE COMPARTMENT))
*a Component with harness connected
(Certification ECU (Smart Key ECU Assembly))*b Waveform 1 - Using an oscilloscope, check the waveform.
OK
Tester Connection Condition Tool Setting Specified Condition N9-13 (CLG8) - G47-18 (E) Procedure: - Power switch off
- Electrical key transmitter sub-assembly brought outside vehicle
- All doors closed
- Luggage electrical key switch off → on
2 V/DIV., 500 ms/DIV. Pulse generation
(See waveform 1)N9-12 (CG8B) - G47-18 (E) Procedure: - Power switch off
- Electrical key transmitter sub-assembly brought outside vehicle
- All doors closed
- Luggage electrical key switch off → on
2 V/DIV., 500 ms/DIV. Pulse generation
(See waveform 1)Result
Proceed to OK NG
Result:
OK
REPLACE ELECTRICAL KEY ANTENNA (OUTSIDE LUGGAGE COMPARTMENT). Refer to REMOVAL [06/2018 - 08/2021] , or refer to REMOVAL [08/2021 - 09/2022] , or refer to REMOVAL [09/2022 - ]
Result:
NG
REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY). Refer to REMOVAL [06/2018 - 08/2021] , or refer to REMOVAL [08/2021 - 09/2022] , or refer to REMOVAL [09/2022 - ]
- Using an oscilloscope, check the waveform.