Toyota Sienna Service Manual: Engine Immobiliser System Malfunction

Toyota Sienna Service Manual / Engine immobiliser / Problem symptoms table / Diagnostic trouble code chart / Engine Immobiliser System Malfunction

DTC B2799 Engine Immobiliser System Malfunction

DESCRIPTION

This DTC is output when the ECM detects errors in communication between the transponder key ECU and the ECM, or in the communication lines. This DTC is also output when an engine start is attempted while the ECU communication ID between the transponder key ECU and the ECM are different. Before troubleshooting for this DTC, make sure that there is no DTC detected in the transponder key ECU. If there is key code-related DTC detected in the transponder key ECU, repair it first.

DTC No.	DTC Detection Condition	Trouble Area
B2799	Error in communication between ECM and transponder key ECU, and in communication line Communication ID is different during communication with transponder key ECU	Wire harness Transponder key ECU assembly Transponder key amplifier ECM

WIRING DIAGRAM

WIRING DIAGRAM

INSPECTION PROCEDURE

1 CHECK HARNESS AND CONNECTOR (TRANSPONDER KEY ECU ASSEMBLY - ECM)

CHECK HARNESS AND CONNECTOR (TRANSPONDER KEY ECU ASSEMBLY - ECM)

Disconnect the T6 ECU and E5 ECM connectors.
Check the resistance of the wire harness side connectors.

Resistance

Resistance

2 CHECK TRANSPONDER KEY ECU ASSEMBLY

After replacing the transponder key ECU assembly with a normally functioning transponder key ECU assembly, check that the engine starts.

OK: The engine starts

END

No Communication in Immobiliser System

DTC B2796 No Communication in Immobiliser System DTC B2798 Communication Malfunction No. 2 DESCRIPTION These codes are stored in the memory when a key that does not have a transponder chip is ins ...

Cruise control

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Other materials:

Removal
1. PRECAUTION CAUTION: Be sure to read "PRECAUTION" thoroughly before servicing. 2. DISCONNECT CABLE FROM NEGATIVE BATTERY TERMINAL CAUTION: Wait for 90 seconds after disconnecting the cable to prevent the airbag working. 3. REMOVE INSTRUMENT PANEL FINISH PANEL SUBASSEMBLY LOWER L ...

ECM Power Source Circuit
DESCRIPTION When the ignition switch is turned to the ON position, the battery voltage is applied to terminal IGSW of the ECM. The ECM MREL output signal causes a current to flow to the coil, closing the contacts of the EFI relay and supplying power to terminal +B of the ECM. If the igniti ...

Disassembly
1. REMOVE NO. 1 HEADLIGHT BULB (HALOGEN HEADLIGHT) Turn in the direction indicated by the arrow and remove the No. 1 headlight bulb. 2. REMOVE DISCHARGE HEADLIGHT BULB (DISCHARGE HEADLIGHT) Turn in the direction indicated by the arrow and disconnect the socket. ...