Dtc B2796 No Communication In Immobiliser System

Land Cruiser URJ200 URJ202 GRJ200 VDJ200 - THEFT DETERRENT / KEYLESS ENTRY

DESCRIPTION

WIRING DIAGRAM

INSPECTION PROCEDURE

CLEAR DTC

CHECK FOR DTC

CHECK CONNECTION OF CONNECTOR

CHECK WHETHER ENGINE STARTS

CLEAR DTC

CHECK FOR DTC

CHECK TRANSPONDER KEY AMPLIFIER

CHECK TRANSPONDER KEY AMPLIFIER (VC5)

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

CHECK TRANSPONDER KEY AMPLIFIER (TXCT)

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

CHECK TRANSPONDER KEY AMPLIFIER (CODE)

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

DTC B2796 No Communication in Immobiliser System

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 CodeDTC Detection ConditionTrouble AreaDTC Output Confirmation Operation
B2796The key code cannot be transmitted (1 trip detection logic*).
Key
Harness or connector
Transponder key ECU assembly
Transponder key amplifier
Insert the key into the ignition key cylinder.
*: Only output while a malfunction is present.
Vehicle Condition and Fail-safe Operation when Malfunction Detected
Vehicle Condition when Malfunction DetectedFail-safe Operation when Malfunction Detected
Engine cannot be started-
Related Data List and Active Test
DTC CodeData List and Active Test
B2796Response

WIRING DIAGRAM

Dtc B2796 No Communication In Immobiliser System. THEFT DETERRENT / KEYLESS ENTRY. Land Cruiser URJ200 URJ202 GRJ200 VDJ200

INSPECTION PROCEDURE

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

Clear the DTCs ().

NEXT
2.CHECK FOR DTC

Insert and remove each registered key one at a time, and check for DTCs each time ().

  • HINT:
Before checking for DTCs, perform the "DTC Output Confirmation Operation" procedure.
If DTC B2796 is output, check for DTCs with the next key after clearing the DTCs.
  • OK:
  • DTC B2796 is not output.
Result
ResultProceed to
OKA
NG (all keys)B
NG (any key)C
B
Go to step 3
C
REPLACE KEY THAT CANNOT START ENGINE
A
USE SIMULATION METHOD TO CHECK ()
3.CHECK CONNECTION OF CONNECTOR

Check the connection of the transponder key ECU assembly and transponder key amplifier connectors.

Visually inspect the terminals of the transponder key ECU assembly and transponder key amplifier connectors.

  • OK:
  • Connectors are properly connected.
NG
CONNECT CONNECTORS PROPERLY
OK
4.CHECK WHETHER ENGINE STARTS

Check that the engine starts with an already registered vehicle key.

  • OK:
  • Engine starts normally.
NG
Go to step 7
OK
5.CLEAR DTC

Clear the DTCs ().

NEXT
6.CHECK FOR DTC

Check for DTCs ().

  • HINT:
  • Before checking for DTCs, perform the "DTC Output Confirmation Operation" procedure.
  • OK:
  • DTC B2796 is not output.
NG
Go to step 7
OK
END (CONNECTOR WAS NOT PROPERLY CONNECTED)
7.CHECK TRANSPONDER KEY AMPLIFIER
Dtc B2796 No Communication In Immobiliser System. THEFT DETERRENT / KEYLESS ENTRY. Land Cruiser URJ200 URJ202 GRJ200 VDJ200

Using an oscilloscope, check the waveform.


Waveform 1 (Reference)

Measurement Condition
ItemContent
Tester ConnectionE95-1 (VC5) - Body ground
Tool Setting1 V/DIV., 20 ms./DIV.
ConditionKey inserted in ignition key cylinder

Waveform 2 (Reference)

Measurement Condition
ItemContent
Tester ConnectionE95-5 (TXCT) - Body ground
Tool Setting1 V/DIV., 20 ms./DIV.
ConditionKey inserted in ignition key cylinder

Waveform 3 (Reference)

Measurement Condition
ItemContent
Tester ConnectionE95-4 (CODE) - Body ground
Tool Setting1 V/DIV., 20 ms./DIV.
ConditionKey inserted in ignition key cylinder
  • OK:
  • Waveform is output normally (refer to illustration).
Text in Illustration
*aComponent with harness connected
(Transponder Key Amplifier)
*bWaveform 1
*cWaveform 2
*dWaveform 3
Result
ResultProceed to
OKA
NG (Waveform 1)B
NG (Waveform 2)C
NG (Waveform 3)D
B
Go to step 8
C
Go to step 10
D
Go to step 12
A
REPLACE TRANSPONDER KEY ECU ASSEMBLY
8.CHECK TRANSPONDER KEY AMPLIFIER (VC5)

Disconnect the E95 transponder key amplifier connector.

Dtc B2796 No Communication In Immobiliser System. THEFT DETERRENT / KEYLESS ENTRY. Land Cruiser URJ200 URJ202 GRJ200 VDJ200

Using an oscilloscope, check the waveform.


Waveform (Reference)

Measurement Condition
ItemContent
Tester ConnectionE95-1 (VC5) - Body ground
Tool Setting1 V/DIV., 20 ms./DIV.
ConditionKey inserted in ignition key cylinder
  • OK:
  • Waveform is output normally (refer to illustration).
Text in Illustration
*aFront view of wire harness connector
(to Transponder Key Amplifier)
*bWaveform
NG
Go to step 9
OK
REPLACE TRANSPONDER KEY AMPLIFIER ()
9.CHECK HARNESS AND CONNECTOR (TRANSPONDER KEY AMPLIFIER - TRANSPONDER KEY ECU ASSEMBLY)

Disconnect the E95 transponder key amplifier connector.

Disconnect the E96 transponder key ECU assembly connector.

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

  • Standard Resistance:
  • Tester ConnectionConditionSpecified Condition
    E95-1 (VC5) - E96-14 (VC5)AlwaysBelow 1 Ω
    E95-7 (AGND) - E96-5 (AGND)AlwaysBelow 1 Ω
    E95-1 (VC5) - Body groundAlways10 kΩ or higher
NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK
REPLACE TRANSPONDER KEY ECU ASSEMBLY
10.CHECK TRANSPONDER KEY AMPLIFIER (TXCT)

Disconnect the E95 transponder key amplifier connector.

Dtc B2796 No Communication In Immobiliser System. THEFT DETERRENT / KEYLESS ENTRY. Land Cruiser URJ200 URJ202 GRJ200 VDJ200

Using an oscilloscope, check the waveform.


Waveform (Reference)

Measurement Condition
ItemContent
Tester ConnectionE95-5 (TXCT) - Body ground
Tool Setting1 V/DIV., 20 ms./DIV.
ConditionKey inserted in ignition key cylinder
  • OK:
  • Waveform is output normally (refer to illustration).
Text in Illustration
*aFront view of wire harness connector
(to Transponder Key Amplifier)
*bWaveform
NG
Go to step 11
OK
REPLACE TRANSPONDER KEY AMPLIFIER ()
11.CHECK HARNESS AND CONNECTOR (TRANSPONDER KEY AMPLIFIER - TRANSPONDER KEY ECU ASSEMBLY)

Disconnect the E95 transponder key amplifier connector.

Disconnect the E96 transponder key ECU assembly connector.

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

  • Standard Resistance:
  • Tester ConnectionConditionSpecified Condition
    E95-5 (TXCT) - E96-4 (TXCT)AlwaysBelow 1 Ω
    E95-5 (TXCT) - Body groundAlways10 kΩ or higher
NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK
REPLACE TRANSPONDER KEY ECU ASSEMBLY
12.CHECK TRANSPONDER KEY AMPLIFIER (CODE)

Disconnect the E95 transponder key amplifier connector.

Dtc B2796 No Communication In Immobiliser System. THEFT DETERRENT / KEYLESS ENTRY. Land Cruiser URJ200 URJ202 GRJ200 VDJ200

Using an oscilloscope, check the waveform.


Waveform (Reference)

Measurement Condition
ItemContent
Tester ConnectionE95-4 (CODE) - Body ground
Tool Setting1 V/DIV., 20 ms./DIV.
ConditionKey inserted in ignition key cylinder
  • OK:
  • Waveform is output normally (refer to illustration).
Text in Illustration
*aFront view of wire harness connector
(to Transponder Key Amplifier)
*bWaveform
NG
Go to step 13
OK
REPLACE TRANSPONDER KEY AMPLIFIER ()
13.CHECK HARNESS AND CONNECTOR (TRANSPONDER KEY AMPLIFIER - TRANSPONDER KEY ECU ASSEMBLY)

Disconnect the E95 transponder key amplifier connector.

Disconnect the E96 transponder key ECU assembly connector.

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

  • Standard Resistance:
  • Tester ConnectionConditionSpecified Condition
    E95-4 (CODE) - E96-15 (CODE)AlwaysBelow 1 Ω
    E95-4 (CODE) - Body groundAlways10 kΩ or higher
NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK
REPLACE TRANSPONDER KEY ECU ASSEMBLY