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DTC    B2799    Engine Immobiliser System Malfunction

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DESCRIPTION

This DTC is stored when one of the following occurs: 1) the power management control ECU (HV CPU) detects an error in its own communication with the certification ECU assembly (smart key ECU assembly)*1 or ID code box (immobiliser code ECU)*2; 2) the power management control ECU (HV CPU) detects an error in the communication lines; or 3) the ECU communication ID between the certification ECU assembly (smart key ECU assembly)*1 or ID code box (immobiliser code ECU)*2 and power management control ECU (HV CPU) is different and a hybrid vehicle control system start is attempted.
  1. *1: w/o Airbag Cut-off Switch
  2. *2: w/ Airbag Cut-off Switch

HINT:
Before troubleshooting this DTC, make sure that no certification ECU (smart key ECU assembly) DTCs are present. If present, troubleshoot the certification ECU (smart key ECU assembly) DTCs first.


DTC No.
DTC Detection Condition
Trouble Area
B2799
One of the following conditions is met:
  1. Error in communication between power management control ECU (HV CPU) and certification ECU assembly (smart key ECU assembly)*1 or ID code box (immobiliser code ECU)*2
  2. Error in communication lines
  3. Communication ID is different between certification ECU assembly (smart key ECU assembly)*1 or ID code box (immobiliser code ECU)*2 and power management control ECU (HV CPU) during communication
  1. Wire harness or connector
  2. Power management control ECU (HV CPU)
  3. Certification ECU (Smart key ECU assembly)*1
  4. ID code box (Immobiliser code ECU)*2
  1. *1: w/o Airbag Cut-off Switch
  2. *2: w/ Airbag Cut-off Switch

WIRING DIAGRAM


w/o Airbag Cut-off Switch

B219131E08


w/ Airbag Cut-off Switch

B219131E07


INSPECTION PROCEDURE

NOTICE:
  1. If the certification ECU (smart key ECU assembly) is replaced, register all the keys and ECU communication ID.*1
  2. If the ID code box (immobiliser code ECU) is replaced, register the ECU code and ECU communication ID.*2
    1. *1: w/o Airbag Cut-off Switch
    2. *2: w/ Airbag Cut-off Switch

1.CHECK DTC OUTPUT

  1. Clear the DTCs (Click here).

  1. Recheck for DTCs (Click here).

    OK:
    DTC B2799 is not output.



NG
Go to step 2
OK

USE SIMULATION METHOD TO CHECK (Click here)  

2.RE-REGISTER ECU COMMUNICATION ID

  1. Re-register the ECU communication ID.


NEXT


3.CHECK DTC OUTPUT

  1. Clear the DTCs (Click here).

  1. Recheck for DTCs (Click here).

    OK:
    DTC B2799 is not output.



NG
Go to step 4
OK

END (ECU COMMUNICATION ID WAS NOT REGISTERED CORRECTLY) 

4.CHECK CONNECTOR CONNECTION CONDITION

  1. Turn the power switch off.

  1. Check that the connectors are properly connected to the power management control ECU (HV CPU) and certification ECU (smart key ECU assembly)*1 or ID code box (immobiliser code ECU)*2.

    1. *1: w/o Airbag Cut-off Switch
    2. *2: w/ Airbag Cut-off Switch

    OK:
    Connectors are properly connected.



NG
CONNECT CONNECTORS PROPERLY
OK


5.SYSTEM CHECK

  1. Check the vehicle specification.

    Result:
    Result
    		Proceed to
    w/o Airbag Cut-off Switch
    		A
    w/ Airbag Cut-off Switch
    		B



B
Go to step 9
A


6.CHECK HARNESS AND CONNECTOR (CERTIFICATION ECU - POWER MANAGEMENT CONTROL ECU (HV CPU))

  1. Disconnect the certification ECU (smart key ECU assembly) connector.



    B229596E01

  1. Disconnect the power management control ECU (HV CPU) connector.

  1. Measure the resistance and voltage according to the value(s) in the table below.

    Standard Resistance:
    Tester Connection
    		Condition
    		Specified Condition
    L62-34 (EFII) - L6-20 (IMO)
    		Always
    		Below 1 Ω
    L62-35 (EFIO) - L6-21 (IMI)
    		Always
    		Below 1 Ω
    L6-20 (IMO) - Body ground
    		Always
    		10 kΩ or higher
    L6-21 (IMI) - Body ground
    		Always
    		10 kΩ or higher

    Standard Voltage:
    Tester Connection
    		Condition
    		Specified Condition
    L6-20 (IMO) - Body ground
    		Always
    		Below 1 V
    L6-21 (IMI) - Body ground
    		Always
    		Below 1 V

    Text in Illustration 
    *1
    		Front view of wire harness connector
    (to Certification ECU (Smart Key ECU Assembly))
    *2
    		Front view of wire harness connector
    (to Power Management Control ECU (HV CPU))



NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK


7.REPLACE POWER MANAGEMENT CONTROL ECU (HV CPU)

  1. Replace the power management control ECU (HV CPU) (Click here).


NEXT


8.CHECK DTC OUTPUT

  1. Clear the DTCs (Click here).

  1. Recheck for DTCs (Click here).

    OK:
    DTC B2799 is not output.



NG
REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)
OK

END (POWER MANAGEMENT CONTROL ECU (HV CPU) WAS DEFECTIVE) 

9.CHECK HARNESS AND CONNECTOR (ID CODE BOX - POWER MANAGEMENT CONTROL ECU (HV CPU))

  1. Disconnect the ID code box (immobiliser code ECU) connector.



    B219313E03

  1. Disconnect the power management control ECU (HV CPU) connector.

  1. Measure the resistance and voltage according to the value(s) in the table below.

    Standard Resistance:
    Tester Connection
    		Condition
    		Specified Condition
    L10-5 (EFII) - L6-20 (IMO)
    		Always
    		Below 1 Ω
    L10-6 (EFIO) - L6-21 (IMI)
    		Always
    		Below 1 Ω
    L6-20 (IMO) - Body ground
    		Always
    		10 kΩ or higher
    L6-21 (IMI) - Body ground
    		Always
    		10 kΩ or higher

    Standard Voltage:
    Tester Connection
    		Condition
    		Specified Condition
    L6-20 (IMO) - Body ground
    		Always
    		Below 1 V
    L6-21 (IMI) - Body ground
    		Always
    		Below 1 V

    Text in Illustration 
    *1
    		Front view of wire harness connector
    (to ID Code Box (Immobiliser Code ECU))
    *2
    		Front view of wire harness connector
    (to Power Management Control ECU (HV CPU))



NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK


10.REPLACE POWER MANAGEMENT CONTROL ECU (HV CPU)

  1. Replace the power management control ECU (HV CPU) (Click here).


NEXT


Go to step 7

11.CHECK DTC OUTPUT

  1. Clear the DTCs (Click here).

  1. Recheck for DTCs (Click here).

    OK:
    DTC B2799 is not output.



NG
REPLACE ID CODE BOX (IMMOBILISER CODE ECU)
OK

END (POWER MANAGEMENT CONTROL ECU (HV CPU) WAS DEFECTIVE)