DTC B27A7: Open in Inside Luggage Compartment Electrical Key Oscillator Circuit [08/2019 - ]: Procedure
WARNING: This page is about a different car, the 2022 Toyota Sequoia, 2021 Toyota Sequoia, and 2020 Toyota Sequoia. 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 No. 1 indoor electrical key antenna assembly (inside luggage compartment).
Result
Result Proceed to The connectors are properly connected A The connectors are not properly connected B
Result:
B
CONNECT CONNECTORS PROPERLY
Result:
A
See step 2
- Check that the connectors are properly connected to the certification ECU (smart key ECU assembly) and No. 1 indoor electrical key antenna assembly (inside luggage compartment).
- CHECK HARNESS AND CONNECTOR (CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) - NO. 1 INDOOR ELECTRICAL KEY ANTENNA ASSEMBLY (INSIDE LUGGAGE COMPARTMENT))
- Disconnect the H198 certification ECU (smart key ECU assembly) connector.
- Disconnect the O62 No. 1 indoor electrical key antenna assembly (inside luggage compartment) connector.
- Measure the resistance according to the value(s) in the table below.
Standard Resistance
Tester Connection Condition Specified Condition H198-4 (CLG7) - O62-1 (ANTE7) Always Below 1 Ω H198-3 (CG7B) - O62-2 (CLGB) Always Below 1 Ω - Reconnect the H198 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 NO. 1 INDOOR ELECTRICAL KEY ANTENNA ASSEMBLY (INSIDE LUGGAGE COMPARTMENT))
*a Component with harness connected
(Certification ECU (Smart Key ECU Assembly))*b Waveform *c For 30 seconds after any door closed *d After 30 seconds or more have elapsed since any door closed - Using an oscilloscope, check the waveform.
OK
Tester Connection Condition Tool Setting Specified Condition H198-4 (CLG7) - H199-11 (E) Procedure: - Engine switch off
- Electrical key transmitter sub-assembly not inside vehicle
- Within 30 seconds of closing any door
2 V/DIV., 500 ms/DIV. Pulse generation
(See waveform)H198-3 (CG7B) - H199-11 (E) Procedure: - Engine switch off
- Electrical key transmitter sub-assembly not inside vehicle
- Within 30 seconds of closing any door
2 V/DIV., 500 ms/DIV. Pulse generation
(See waveform)Result
Proceed to OK NG
Result:
OK
REPLACE NO. 1 INDOOR ELECTRICAL KEY ANTENNA ASSEMBLY (INSIDE LUGGAGE COMPARTMENT). Refer to REMOVAL [08/2019 - ]
Result:
NG
REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY). Refer to REMOVAL [08/2019 - ]
- Using an oscilloscope, check the waveform.