DTC    B2799    Engine Immobiliser System Malfunction

for Preparation Click here


DESCRIPTION

When there are communication malfunctions between the power management control ECU and ID code box (immobiliser code ECU), or when the communication ID codes do not match, the power management control ECU stores this DTC.

DTC Code
DTC Detection Condition
Trouble Area
DTC Output Confirmation Operation
B2799
Either condition is met (1 trip detection logic*):
  1. A malfunction in the communication or communication lines between the power management control ECU and ID code box (immobiliser code ECU).
  2. A matching communication code cannot be verified during communication between the power management control ECU and ID code box (immobiliser code ECU).
  1. ID code box (immobiliser code ECU)
  2. Power management control ECU
  3. Wire harness or connector
Either condition is met:
  1. Within 10 seconds of a hybrid control system start operation being performed (with park (P) selected and the brake pedal depressed, press the power switch while carrying the key). If there is a malfunction, the hybrid control system stops (communication begins within 3 seconds of the hybrid control system start operation being performed, and DTCs are stored after 6 seconds).
  2. 10 seconds after the power switch is turned on (IG) after reconnecting the cable to the negative (-) terminal of the auxiliary battery (communication begins within 3 seconds of the power switch being turned on (IG), and DTCs are stored after 6 seconds).
  1. *: Only output while a malfunction is present.

Vehicle Condition and Fail-safe Operation when Malfunction Detected 
Vehicle Condition when Malfunction Detected
Fail-safe Operation when Malfunction Detected
Hybrid control system cannot be started
-

Related Data List and Active Test 
DTC Code
Data List and Active Test
B2799
-

WIRING DIAGRAM


B235863E20


INSPECTION PROCEDURE

NOTICE:
  1. When replacing the ID code box (immobiliser code ECU), refer to the Service Bulletin.
  2. The fixed 12 V power source voltage in the power management control ECU is output through a resistance from terminal IMI. The ID code box (immobiliser code ECU) grounds or does not ground this power source voltage accordingly.
  3. The fixed 12 V power source voltage in the ID code box (immobiliser code ECU) is output through a resistance from terminal EFII. The power management control ECU grounds or does not ground this power source voltage accordingly.
  4. After performing repair, perform the operation that fulfills the DTC output confirmation operation, and then confirm that no DTCs are output again.

HINT:
When DTC B2799 and a DTC for the certification ECU (smart key ECU assembly) are output simultaneously, first perform troubleshooting for the certification ECU (smart key ECU assembly) DTC.

1.CLEAR DTC

  1. Clear the DTCs (Click here).


NEXT


2.CHECK FOR DTC

  1. Check for DTCs (Click here).

    HINT:
    Before checking for DTCs, perform the "DTC Output Confirmation Operation" procedure.

    OK:
    DTC B2799 is not output.



NG
Go to step 3
OK

USE SIMULATION METHOD TO CHECK (Click here)  

3.CHECK POWER MANAGEMENT CONTROL ECU (IMO)


  1. Using an oscilloscope, check the waveform.


    B270935E01


    Text in Illustration 
    *1
    		Waveform 1
    		-
    		-
    *a
    		Component with harness connected
    (Power Management Control ECU)
    		*b
    		Normal Waveform
    Measurement Condition 
    Item
    		Content
    Tester Connection
    		H4-20 (IMO) - Body ground
    Tool Setting
    		2 V/DIV., 200 ms./DIV.
    Condition
    		Within 3 seconds of hybrid control system start or within 3 seconds of power switch turned on (IG) after auxiliary battery cable disconnected and reconnected

    HINT:
    The waveform shown in the illustration is an example for reference only. Noise, chattering, etc. are not shown.

    OK:
    Waveform is output normally (refer to illustration).

    Result 
    Result
    		Proceed to
    Normal waveform
    		A
    Waveform 1 has abnormal wavelength or shape
    		B
    Terminal IMO stuck high (12 V)
    Terminal IMO stuck low (2.4 V or less)
    		C



B
Go to step 7

C
Go to step 10
A


4.CHECK POWER MANAGEMENT CONTROL ECU (IMI)


  1. Using an oscilloscope, check the waveform.


    B270934E01


    Text in Illustration 
    *1
    		Waveform 2
    		-
    		-
    *a
    		Component with harness connected
    (Power Management Control ECU)
    		*b
    		Normal Waveform
    Measurement Condition 
    Item
    		Content
    Tester Connection
    		H4-21 (IMI) - Body ground
    Tool Setting
    		2 V/DIV., 200 ms./DIV.
    Condition
    		Power switch on (IG)

    HINT:
    The waveform shown in the illustration is an example for reference only. Noise, chattering, etc. are not shown.

    OK:
    Waveform is output normally (refer to illustration).

    Result 
    Result
    		Proceed to
    Normal waveform
    		A
    Waveform 2 not output, or has abnormal wavelength or shape
    		B



B
Go to step 12
A


5.REGISTER RECOGNITION CODES

  1. Register the recognition codes in the ECUs.


NEXT


6.REGISTER ECU COMMUNICATION ID

  1. Register the ECU communication ID.

  1. Check that the hybrid control system can be started with a registered key.

    OK:
    Hybrid control system can be started with a registered key.



NG
Go to step 7
OK

END (ECU COMMUNICATION ID WAS NOT REGISTERED CORRECTLY) 

7.REPLACE POWER MANAGEMENT CONTROL ECU

  1. Temporarily replace the power management control ECU with a new or known good one (Click here).


NEXT


8.CLEAR DTC

  1. Clear the DTCs (Click here).


NEXT


9.CHECK FOR DTC

  1. Check for DTCs (Click here).

    HINT:
    Before checking for DTCs, perform the "DTC Output Confirmation Operation" procedure.

    OK:
    DTC is not output.



NG
GO TO DIAGNOSTIC TROUBLE CODE CHART (Click here)
OK

END (POWER MANAGEMENT CONTROL ECU WAS DEFECTIVE) 

10.CHECK ID CODE BOX (IMMOBILISER CODE ECU) (IMO)

  1. Disconnect the H4 ECU connector.

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

    Standard Voltage:
    Tester Connection
    		Condition
    		Specified Condition
    H4-20 (IMO) - Body ground
    		Power switch on (IG)
    		11 to 14 V



B
Go to step 15
A


11.CHECK HARNESS AND CONNECTOR (ID CODE BOX - POWER MANAGEMENT CONTROL ECU)

  1. Disconnect the H22 box connector.

  1. Disconnect the H4 ECU connector.

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

    Standard Resistance:
    Tester Connection
    		Condition
    		Specified Condition
    H22-5 (EFII) - H4-20 (IMO)
    		Always
    		Below 1 Ω
    H4-20 (IMO) - Body ground
    		Always
    		10 kΩ or higher



NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK


12.REPLACE ID CODE BOX (IMMOBILISER CODE ECU)

  1. Replace the ID code box (immobiliser code ECU) with a new one.


NEXT


13.CLEAR DTC

  1. Clear the DTCs (Click here).

  1. Register the recognition codes in the ECUs.

  1. Register the ECU communication ID.


NEXT


14.CHECK FOR DTC

  1. Check for DTCs (Click here).

    HINT:
    Before checking for DTCs, perform the "DTC Output Confirmation Operation" procedure.

    OK:
    DTC is not output.



NG
GO TO DIAGNOSTIC TROUBLE CODE CHART (Click here)
OK

END (ID CODE BOX (IMMOBILISER CODE ECU) WAS DEFECTIVE) 

15.REPLACE POWER MANAGEMENT CONTROL ECU

  1. Temporarily replace the power management control ECU with a new or known good one (Click here).


NEXT


16.CLEAR DTC

  1. Clear the DTCs (Click here).


NEXT


17.CHECK FOR DTC

  1. Check for DTCs (Click here).

    HINT:
    Before checking for DTCs, perform the "DTC Output Confirmation Operation" procedure.

    OK:
    DTC is not output.



NG
GO TO DIAGNOSTIC TROUBLE CODE CHART (Click here)
OK

END (POWER MANAGEMENT CONTROL ECU WAS DEFECTIVE)