The certification ECU (smart key ECU assembly) generates a request signal and transmits the signal to the No. 1 indoor electrical key antenna assembly (front floor). For the No. 1 indoor electrical key antenna assembly (front floor) to detect when the electrical key transmitter sub-assembly is in the cabin, the signal from the certification ECU (smart key ECU assembly) requesting a response from the electrical key transmitter sub-assembly is transmitted inside the vehicle. DTC B27A5 is stored by the certification ECU (smart key ECU assembly) when an open is detected between the certification ECU (smart key ECU assembly) and No. 1 indoor electrical key antenna assembly (front floor) (between terminals CLG5 and ANTE5, or terminals CG5B and CLGB).
| DTC No. | Detection Item | DTC Detection Condition | Trouble Area | Note |
|---|---|---|---|---|
| B27A5 | Open in Front Floor Electrical Key Oscillator Circuit | An open is detected in the circuit between the certification ECU (smart key ECU assembly) and No. 1 indoor electrical key antenna assembly (front floor) (CLG5 - ANTE5, CG5B - CLGB) (1 trip detection logic*). | ·
Certification ECU (smart key ECU assembly) ·
No. 1 indoor electrical key antenna assembly (front floor) ·
Wire harness or connector |
DTC Output Confirmation Operation:
Any time |
*: Only output while a malfunction is present.
| Vehicle Condition when Malfunction Detected | Fail-safe Operation when Malfunction Detected |
|---|---|
| When electrical key transmitter sub-assembly is in front seat area:
·
Power source mode does not change when engine switch pressed ·
Electrical key transmitter sub-assembly locked inside vehicle |
- |
| DTC No. | Data List and Active Test |
|---|---|
| B27A5 | Key diagnostic mode can be used to perform troubleshooting |
When using the GTS with the engine switch off, connect the GTS to the DLC3 and turn a courtesy light switch on and off at intervals of 1.5 seconds or less until communication between the GTS and the vehicle begins. Then select Model Code "KEY REGIST" under manual mode and enter the following menus: Body Electrical / Entry&Start(CAN). While using the GTS, periodically turn a courtesy light switch on and off at intervals of 1.5 seconds or less to maintain communication between the GTS and the vehicle.
The smart entry and start system (for Start Function) uses the LIN communication system and CAN communication system. Inspect the communication function by following How to Proceed with Troubleshooting. Troubleshoot the smart entry and start system (for Start Function) after confirming that the communication systems are functioning properly.
Before replacing the certification ECU (smart key ECU assembly), refer to Service Bulletin.
After repair, confirm that no DTCs are output by performing "DTC Output Confirmation Operation".
Check that the connectors are properly connected to the certification ECU (smart key ECU assembly) and No. 1 indoor electrical key antenna assembly (front floor).
Connectors are properly connected.
| Proceed to |
|---|
| OK |
| NG |
OK
NG
Disconnect the I1 certification ECU (smart key ECU assembly) connector.
Disconnect the I34 No. 1 indoor electrical key antenna assembly (front floor) connector.
Measure the resistance according to the value(s) in the table below.
| Tester Connection | Condition | Specified Condition |
|---|---|---|
| I1-8 (CLG5) - I34-1 (ANTE5) | Always | Below 1 Ω |
| I1-9 (CG5B) - I34-2 (CLGB) | Always | Below 1 Ω |
Reconnect the I1 certification ECU (smart key ECU assembly) connector.
| Proceed to |
|---|
| OK |
| NG |
OK
NG
| *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.
| Tester Connection | Condition | Tool Setting | Specified Condition |
|---|---|---|---|
| I1-8 (CLG5) - I1-18 (E) | Procedure:
1.
Engine switch off 2.
Electrical key transmitter sub-assembly not inside vehicle 3.
Within 30 seconds of closing any door |
2 V/DIV., 500 ms/DIV. | Pulse generation
(See waveform) |
| I1-9 (CG5B) - I1-18 (E) | Procedure:
1.
Engine switch off 2.
Electrical key transmitter sub-assembly not inside vehicle 3.
Within 30 seconds of closing any door |
2 V/DIV., 500 ms/DIV. | Pulse generation
(See waveform) |
| Proceed to |
|---|
| OK |
| NG |
OK
NG