DESCRIPTION
The certification ECU (smart key ECU assembly) generates a request signal and transmits the signal to the rear door outside handle assembly (for driver side) (electrical key antenna) at intervals of 0.25 seconds. For the rear door outside handle assembly (for driver side) (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 rear door at intervals of 0.25 seconds. DTC B27A3 is stored by the certification ECU (smart key ECU assembly) when an open is detected between the certification ECU (smart key ECU assembly) and rear door outside handle assembly (for driver side) (electrical key antenna) (between terminals CLG3 and ANT1, or terminals CG3B and ANT2).
DTC No. | Detection Item | DTC Detection Condition | Trouble Area | Note |
---|---|---|---|---|
B27A3 | Open in Rear Door Electrical Antenna Circuit, Drivers Side | An open is detected in the circuit between the certification ECU (smart key ECU assembly) and rear door outside handle assembly (for driver side) (CLG3 - ANT1, CG3B - ANT2) (This is detected by the malfunction detection circuit in the certification ECU (smart key ECU assembly)) (1 trip detection logic*). |
|
|
Vehicle Condition when Malfunction Detected | Fail-safe Operation when Malfunction Detected |
---|---|
Entry lock/unlock operation cannot be performed for rear door (for driver side) | - |
DTC No. | Data List and Active Test |
---|---|
B27A3 | Key diagnostic mode can be used to perform troubleshooting |
WIRING DIAGRAM
CAUTION / NOTICE / HINT
NOTICE:
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PROCEDURE
1. | CHECK CONNECTOR CONNECTION |
(a) Check that the connectors are properly connected to the certification ECU (smart key ECU assembly) and rear door outside handle assembly (for driver side).
OK:
Connectors are properly connected.
NG | CONNECT CONNECTORS PROPERLY |
|
2. | CHECK HARNESS AND CONNECTOR (CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) - REAR DOOR OUTSIDE HANDLE ASSEMBLY (FOR DRIVER SIDE)) |
(a) Disconnect the R1 and J41 certification ECU (smart key ECU assembly) connectors.
(b) Disconnect the P4 rear door outside handle assembly (for driver side) connector.
(c) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
Tester Connection | Condition | Specified Condition |
---|---|---|
R1-1 (CLG3) - P4-4 (ANT1) | Always | Below 1 Ω |
R1-2 (CG3B) - P4-5 (ANT2) | Always | Below 1 Ω |
J41-18 (E) - Body ground | Always | Below 1 Ω |
R1-1 (CLG3) or P4-4 (ANT1) - Body ground | Always | 10 kΩ or higher |
R1-2 (CG3B) or P4-5 (ANT2) - Body ground | Always | 10 kΩ or higher |
(d) Reconnect the R1 and J41 certification ECU (smart key ECU assembly) connectors.
NG | REPAIR OR REPLACE HARNESS OR CONNECTOR |
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3. | CHECK CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) (OUTPUT TO REAR DOOR OUTSIDE HANDLE ASSEMBLY (FOR DRIVER SIDE)) |
*a | Component with harness connected (Certification ECU (Smart Key ECU Assembly)) | *b | Waveform 1 |
*c | Waveform 2 | *d | Waveform 3 |
*e | Waveform 4 | - | - |
(a) Using an oscilloscope, check the waveform.
OK:
Tester Connection | Condition | Tool Setting | Specified Condition |
---|---|---|---|
R1-1 (CLG3) - J41-18 (E) | Procedure:
| 5 V/DIV., 500 ms/DIV. | Pulse generation (See waveform 1) |
Procedure:
| 5 V/DIV., 100 ms/DIV. | Pulse generation (See waveform 2) | |
R1-2 (CG3B) - J41-18 (E) | Procedure:
| 5 V/DIV., 500 ms/DIV. | Pulse generation (See waveform 3) |
Procedure:
| 5 V/DIV., 100 ms/DIV. | Pulse generation (See waveform 4) |
Click here
NG | REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) |
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4. | REPLACE REAR DOOR OUTSIDE HANDLE ASSEMBLY (FOR DRIVER SIDE) |
(a) Replace the rear door outside handle assembly (for driver side) with a new one or the rear door outside handle assembly (for front passenger side) if it is functioning properly.
Click here
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5. | CLEAR DTC |
(a) Clear the DTCs.
Body Electrical > Smart Access > Clear DTCs
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6. | CHECK FOR DTC |
(a) Check for DTCs.
Body Electrical > Smart Access > Trouble CodesOK:
DTC B27A3 is not output.
OK | END (REAR DOOR OUTSIDE HANDLE ASSEMBLY (FOR DRIVER SIDE) WAS DEFECTIVE) |
NG | REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) |
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