ENGINE IMMOBILISER SYSTEM(w/o Power Switch), Diagnostic DTC:B2799

DTC Code DTC Name
B2799 Engine Immobiliser System Malfunction

DESCRIPTION

This DTC is stored when one of the following occurs: 1) the power management control ECU detects errors in its own communications with the transponder key ECU assembly; 2) the power management control ECU detects errors in the communication lines; or 3) the ECU communication ID between the transponder key ECU assembly and power management control ECU is different and a hybrid control system start is attempted. Before troubleshooting for this DTC, make sure no engine immobiliser DTCs are output. If output, troubleshoot the engine immobiliser DTCs first.

DTC Code DTC Detection Condition Trouble Area DTC Output Confirmation Operation
B2799

Either condition is met (1 trip detection logic*):


  • A malfunction occurs in the communication or communication lines between the power management control ECU and transponder key ECU assembly.

  • A communication code cannot be verified during communication between the power management control ECU and transponder key ECU assembly.


  • Harness or connector

  • Transponder key ECU assembly

  • Power management control ECU

Either condition is met:


  • 10 seconds after a hybrid control system start operation being performed (with the shift lever in P and the brake pedal depressed, turn the ignition switch to ON). 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).

  • 10 seconds after the ignition switch is turned to ON after reconnecting the cable to the negative (-) auxiliary battery terminal (communication begins within 3 seconds of the ignition switch being turned to ON, and DTCs are stored after 6 seconds).


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

A01UZRVE39
*1 Power Management Control ECU
*2 Transponder Key ECU Assembly

CAUTION / NOTICE / HINT

Note


  • When replacing the transponder key ECU assembly, refer to Service Bulletin.

  • After performing repairs, perform the operation that fulfills the DTC output confirmation operation, and then confirm that no DTCs are output again.

PROCEDURE


  1. CLEAR DTC


    1. Clear the DTCs Click here.


    NEXT
  2. CHECK FOR DTC


    1. Start the hybrid control system.

    2. Wait 10 seconds or more.

    3. Check for DTCs Click here.

      Tech Tips

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

      OK
      DTC B2799 is not output.
      Result
      Result Proceed to
      OK A
      NG (DTC B2799 is output) B
      NG (Other DTCs are output) C

    A
    C
    B
  3. INSPECT POWER MANAGEMENT CONTROL ECU (TERMINAL IMO)


    1. Using an oscilloscope, check the waveform.

      A01UY68E02
      Text in Illustration
      *a

      Component with harness connected

      (Power Management Control ECU)

      *b Waveform
      Measurement Condition
      Item Content
      Tester Connection F56-20 (IMO) - Body ground
      Tool Setting 2 V/DIV., 500 ms./DIV.
      Condition Within 3 seconds after hybrid control system starts, or within 3 seconds after ignition switch first turned to ON after auxiliary battery disconnected and reconnected
      OK
      Waveform is output normally (refer to illustration).
      Result
      Result Proceed to
      Normal waveform A
      Terminal IMO stuck low (2.4 V or less) B
      Terminal IMO stuck high (12 V) or Abnormal waveform C

    B
    C
    A
  4. INSPECT POWER MANAGEMENT CONTROL ECU (TERMINAL IMI)


    1. Using an oscilloscope, check the waveform.

      A01UXO7E02
      Text in Illustration
      *a

      Component with harness connected

      (Power Management Control ECU)

      *b Waveform
      Measurement Condition
      Item Content
      Tester Connection F56-21 (IMI) - Body ground
      Tool Setting 2 V/DIV., 500 ms./DIV.
      Condition Within 3 seconds after hybrid control system starts, or within 3 seconds after ignition switch first turned to ON after auxiliary battery disconnected and reconnected
      OK
      Waveform is output normally (refer to illustration).
      Result
      Result Proceed to
      Normal waveform A
      Not output waveform or abnormal waveform B

    B
    A
  5. REGISTER ECU COMMUNICATION ID


    1. Reregister the ECU communication ID (Refer to Service Bulletin).


    NEXT
  6. CHECK WHETHER HYBRID CONTROL SYSTEM STARTS


    1. Check that the hybrid control system starts with an already registered vehicle key.

      OK
      Hybrid control system starts normally.

    OK
    NG
  7. INSPECT POWER MANAGEMENT CONTROL ECU (IMO TERMINAL VOLTAGE)


    1. A01UZETE02
      Text in Illustration
      *a

      Rear view of wire harness connector

      (to Power Management Control ECU)

      Disconnect the power management control ECU connector.

    2. Turn the ignition switch to ON.

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

      Result
      Result Proceed to
      Terminal IMO stuck low (2.4 V or less) A
      Terminal IMO stuck high (12 V) B

    B
    A
  8. CHECK HARNESS AND CONNECTOR (TRANSPONDER KEY ECU - POWER MANAGEMENT CONTROL ECU AND BODY GROUND)


    1. Disconnect the F40 transponder key ECU assembly connector.

    2. Disconnect the F56 power management control ECU connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      F40-12 (EFII) - F56-20 (IMO) Always Below 1 Ω
      F40-12 (EFII) - Body ground Always 10 kΩ or higher

    NG
    OK
  9. REPLACE TRANSPONDER KEY ECU ASSEMBLY


    1. Replace the transponder key ECU assembly with a new one (Refer to Service Bulletin).


    NEXT
  10. REGISTER KEY


    1. Reregister the key (Refer to Service Bulletin).


    NEXT
  11. REGISTER ECU COMMUNICATION ID


    1. Reregister the ECU communication ID (Refer to Service Bulletin).


    NEXT
  12. CHECK WHETHER HYBRID CONTROL SYSTEM STARTS


    1. Check that the hybrid control system starts with an already registered vehicle key.

      OK
      Hybrid control system starts normally.

    OK
    NG
  13. REPLACE POWER MANAGEMENT CONTROL ECU


    1. Temporarily replace the power management control ECU with a new one Click here.


    NEXT
  14. REGISTER ECU COMMUNICATION ID


    1. Reregister the ECU communication ID (Refer to Service Bulletin).


    NEXT
  15. CHECK WHETHER HYBRID CONTROL SYSTEM STARTS


    1. Check that the hybrid control system starts with an already registered vehicle key.

      OK
      Hybrid control system starts normally.

    OK
    NG