Dtc B2796 No Communication In Immobiliser System

Vehicle Interior. Hilux. Tgn26, 36 Kun25, 26, 35, 36 Ggn25
Theft Deterrent Keyless Entry. Hilux. Tgn26, 36 Kun25, 26, 35, 36 Ggn25

DESCRIPTION

WIRING DIAGRAM

INSPECTION PROCEDURE

CLEAR DTC

CHECK FOR DTC

READ VALUE USING INTELLIGENT TESTER (ENGINE IMMOBILISER SYSTEM)

CHECK WHETHER ENGINE STARTS WITH OTHER KEY

CHECK HARNESS AND CONNECTOR (TRANSPONDER KEY ECU - TRANSPONDER KEY AMPLIFIER)

REPLACE TRANSPONDER KEY AMPLIFIER

CHECK WHETHER ENGINE STARTS

DTC B2796 No Communication in Immobiliser System

DTC B2798 Communication Malfunction No. 2


DESCRIPTION

DTC B2796 is stored when a key is inserted into the ignition key cylinder but no communication occurs between the key and transponder key ECU assembly.
DTC B2798 is stored when a key is inserted into the ignition key cylinder but a communication error occurs between the key and transponder key ECU assembly.

DTC Code
DTC Detection Condition
Trouble Area
DTC Output Confirmation Operation
B2796
The key code cannot be transmitted (1 trip detection logic*).
  1. Key
  2. Transponder key amplifier
  3. Harness or connector
  4. Transponder key ECU assembly
Insert the key into the ignition key cylinder
B2798
Key code identification cannot be completed within the specified time (1 trip detection logic*).
Key
Insert the key into the ignition key cylinder
  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
Engine cannot be started.
-

Related Data List and Active Test
DTC Code
Data List and Active Test
B2796
Response
B2798
Frame Error

WIRING DIAGRAM


Hilux. Tgn26, 36 Kun25, 26, 35, 36 Ggn25.Theft Deterrent Keyless Entry.Engine Immobiliser System.
Dtc
  B2796  No Communication In Immobiliser System


INSPECTION PROCEDURE

NOTICE:
  1. When replacing the transponder key ECU assembly, refer to the Service Bulletin.
  2. After performing repairs, perform the operation that fulfills the DTC output confirmation operation, and then confirm that no DTCs are output again.
1.CLEAR DTC
  1. Clear the DTCs (HILUX_TGN26 RM000000Z3I00TX.html).


NEXT


2.CHECK FOR DTC
  1. Check for DTCs (HILUX_TGN26 RM000000Z3I00TX.html).

    OK:
    DTC B2796 or B2798 is not output.


NG
Go to step 3
OK

USE SIMULATION METHOD TO CHECK (HILUX_TGN26 RM000004QR7005X.html)

3.READ VALUE USING INTELLIGENT TESTER (ENGINE IMMOBILISER SYSTEM)
  1. Use the Data List to check if the engine immobiliser system is functioning properly (HILUX_TGN26 RM000000Z3K00SX.html).

    Immobiliser
    Item
    Measurement Item/Range
    Normal Condition
    Diagnostic Note
    Immobiliser
    Engine immobiliser system status determined by transponder key ECU assembly / Set or Unset
    Set: Engine immobiliser set (engine start prohibited [no key in ignition key cylinder])
    Unset: Engine immobiliser unset (engine start permitted [key inserted in ignition key cylinder])
    When the engine immobiliser system does not change to the unset state, this item can be used to determine if the cause is the transponder key ECU assembly.
    OK:
    Set (the key is not inserted in the ignition key cylinder) and Unset (the key is inserted in the ignition key cylinder) appear on the screen according to the key insertion condition.


NG
Go to step 4
OK

REPLACE TRANSPONDER KEY ECU ASSEMBLY

4.CHECK WHETHER ENGINE STARTS WITH OTHER KEY
  1. Check whether the engine starts with an already registered vehicle key.

    OK:
    Engine starts.


NG
Go to step 5
OK

REREGISTER OR REPLACE KEY THAT CANNOT START ENGINE

5.CHECK HARNESS AND CONNECTOR (TRANSPONDER KEY ECU - TRANSPONDER KEY AMPLIFIER)
  1. Disconnect the G26 transponder key ECU assembly connector.

  1. Disconnect the G28 transponder key amplifier connector.

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

    Standard Resistance:
    Tester Connection
    Condition
    Specified Condition
    G26-14 (VC5) - G28-1 (VC5)
    Always
    Below 1 Ω
    G26-15 (CODE) - G28-4 (CODE)
    Always
    Below 1 Ω
    G26-4 (TXCT) - G28-5 (TXCT)
    Always
    Below 1 Ω
    G26-5 (AGND) - G28-7 (AGND)
    Always
    Below 1 Ω
    G26-14 (VC5) or G28-1 (VC5) - Body ground
    Always
    10 kΩ or higher
    G26-15 (CODE) or G28-4 (CODE) - Body ground
    Always
    10 kΩ or higher
    G26-4 (TXCT) or G28-5 (TXCT) - Body ground
    Always
    10 kΩ or higher
    G26-5 (AGND) or G28-7 (AGND) - Body ground
    Always
    10 kΩ or higher


NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK


6.REPLACE TRANSPONDER KEY AMPLIFIER
  1. Temporally replace the transponder key amplifier with a new or normally functioning one (HILUX_TGN26 RM0000037YH01GX.html).


NEXT


7.CHECK WHETHER ENGINE STARTS
  1. Check that the engine starts normally.

    OK:
    Engine starts.


NG
REPLACE TRANSPONDER KEY ECU ASSEMBLY
OK

END (TRANSPONDER KEY AMPLIFIER IS DEFECTIVE)