DTC B27A5 Open in Front Floor Electrical Key Oscillator Circuit |
| DTC Code | DTC Detection Condition | Trouble Area |
| B27A5 | Open is detected in the terminals between the certification ECU and indoor electrical key oscillator (front side) (CLG5 - CLG3, CG5B - CLGB). |
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| 1.CHECK CONNECTOR CONNECTION CONDITION |
Turn the engine switch off.
Check that the connectors are properly connected to the certification ECU and the Indoor electrical key oscillator (front side).
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| OK | |
| 2.CHECK HARNESS AND CONNECTOR (INDOOR ELECTRICAL KEY OSCILLATOR - CERTIFICATION ECU) |
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Disconnect the certification ECU connector.
Disconnect the indoor electrical key oscillator (front side) connector.
Measure the resistance according to the value(s) in the table below.
| Tester Connection | Condition | Specified Condition |
| D32-1 (CLG3) - D34-7 (CLG5) | Always | Below 1 Ω |
| D32-3 (CLGB) - D34-8 (CG5B) | Always | Below 1 Ω |
| D34-7 (CLG5) - Body ground | Always | 10 kΩ or higher |
| D34-8 (CG5B) - Body ground | Always | 10 kΩ or higher |
| *1 | Front view of wire harness connector (to Indoor Electrical Key Oscillator) |
| *2 | Front view of wire harness connector (to Certification ECU) |
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| OK | |
| 3.INSPECT CERTIFICATION ECU |
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Reconnect the certification ECU connector.
Measure the resistance according to the value(s) in the table below.
| Tester Connection | Condition | Specified Condition |
| D34-15 (E) - Body ground | Always | Below 1 Ω |
Measure the pulse generation according to the value(s) in the table below.
| Tester Connection | Condition | Specified Condition |
| D34-7 (CLG5) - D34-15 (E) | Engine switch off, all doors closed, key not in the cabin, and lock sensor off | No pulse generation |
| D34-7 (CLG5) - D34-15 (E) | Engine switch off, all doors closed, key not in the cabin, and lock sensor ON | Pulse generation |
| D34-8 (CG5B) - D34-15 (E) | Engine switch off, all doors closed, key not in the cabin, and lock sensor off | No pulse generation |
| D34-8 (CG5B) - D34-15 (E) | Engine switch off, all doors closed, key not in the cabin, and lock sensor ON | Pulse generation |
| *1 | Component with harness connected (Certification ECU) |
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| OK | |
| 4.REPLACE INDOOR ELECTRICAL KEY OSCILLATOR (FRONT SIDE) |
Temporarily replace the indoor electrical key oscillator (front side) with a new or normally functioning one (Click here).
| NEXT | |
| 5.CHECK DTC OUTPUT |
Clear the DTCs (Click here).
Recheck for DTCs (Click here).
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| OK | ||
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