DTC B2799-542 Engine Immobiliser System Malfunction |
DTC B2799-790 Engine Immobiliser System Malfunction |
| DTC No. | DTC Detection Condition | Trouble Area |
| B2799-542 B2799-790 | Error in communication between hybrid vehicle control ECU and transponder key ECU, and in communication line. Communication ID is different during communication with transponder key ECU. |
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| 1.CHECK HARNESS AND CONNECTOR (TRANSPONDER KEY ECU ASSEMBLY - HYBRID VEHICLE CONTROL ECU) |
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Disconnect the T8 ECU and H29 hybrid vehicle control ECU connectors.
Measure the resistance according to the value(s) in the table below.
| Tester Connection | Specified Condition |
| T8-6 (EFIO) - H29-22 (IMI) | Below 1 Ω |
| T8-7 (EFII) - H29-28 (IMO) | |
| T8-6 (EFIO) or H29-22 (IMI) - Body ground | 10 kΩ or higher |
| T8-7 (EFII) or H29-28 (IMO) - Body ground |
Measure the voltage according to the value(s) in the table below.
| Tester Connection | Condition | Specified Condition |
| T8-6 (EFIO) or H29-22 (IMI) - H32-5 (E1) | Ignition switch on | Below 1 V |
| T8-7 (EFII) or H29-28 (IMO) - H32-5 (E1) |
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| OK | |
| 2.RE-REGISTRATION ECU COMMUNICATION ID (TRANSPONDER KEY ECU ASSEMBLY - HYBRID VEHICLE CONTROL ECU) |
Re-register the ECU communication ID.
Check that the hybrid control system starts.
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| NG | |
| 3.CHECK OPERATION OF TRANSPONDER KEY ECU ASSEMBLY |
After replacing the transponder key ECU assembly with a normally functioning transponder key ECU assembly, check that the hybrid control system starts.
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| OK | ||
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