Toyota RAV4 manuals

Toyota Sienna Service Manual: No Communication in Immobiliser System

DTC B2796 No Communication in Immobiliser System

DTC B2798 Communication Malfunction No. 2

DESCRIPTION

These codes are stored in the memory when a key that does not have a transponder chip is inserted or if communication between the key and transponder key ECU is impossible.

DTC No.

DTC Detection Condition

Trouble Area

B2796

No communication
  • Key
  • Wire harness
  • Transponder key amplifier
  • Transponder key ECU assembly

B2798

Communication error
  • Key

WIRING DIAGRAM

WIRING DIAGRAM

INSPECTION PROCEDURE

1 READ VALUE OF INTELLIGENT TESTER

  1. Connect the intelligent tester (with CAN VIM) to the DLC3.
  2. Turn the ignition switch on and turn the intelligent tester main switch on.
  3. Select IMMOBILISER in the DATA LIST and read the value displayed on the intelligent tester.

Transponder key ECU:

Transponder key ECU

OK: UNSET (Ignition switch on) appears on the screen.

2 CHECK KEYS

  1. Insert the vehicle's other key into the ignition key cylinder.
  2.  Check that the engine starts with this key.

OK: The engine starts

3 READ VALUE OF INTELLIGENT TESTER

  1. Connect the intelligent tester (with CAN VIM) to the DLC3.
  2.  Turn the ignition switch on and turn the intelligent tester main switch on.
  3.  Select ANTENNA COIL in the DATA LIST and read the value displayed on the intelligent tester

Transponder key ECU:

Transponder key ECU

OK: NORMAL (Antenna coil is normal) appears on the screen.

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

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

  1. Disconnect the T6 ECU and I14 amplifier connectors.
  2.  Measure the resistance according to the value(s) in the table below.

Resistance

Resistance

5 INSPECT TRANSPONDER KEY ECU ASSEMBLY

 INSPECT TRANSPONDER KEY ECU ASSEMBLY

  1. Reconnect the T6 ECU and I14 amplifier connectors.
  2.  Measure the voltage according to the value(s) in the table below.

Voltage

Voltage

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

Resistance

Resistance

6 REPLACE TRANSPONDER KEY AMPLIFIER

  1. After replacing the transponder key amplifier with a normally functioning transponder key amplifier, check that the engine starts.

OK: The engine starts.

END (TRANSPONDER KEY AMPLIFIER DEFECTIVE)

DTC B2797 Communication Malfunction No. 1

DESCRIPTION

This DTC is output when an error occurs in normal communication.

HINT: Some noise found in the communication line.

DTC No.

DTC Detection Condition

Trouble Area

B2797

Keys are positioned too close to each other, or noise occurred in communication line.
  • Key
  • Transponder key amplifier
  • Wire harness
  • Transponder key ECU assembly

WIRING DIAGRAM

WIRING DIAGRAM

INSPECTION PROCEDURE

1 CHECK KEY

CHECK KEY

  1. Check whether the ignition key being used is near other ignition keys, as shown in the illustration. Also, check whether the key ring is in contact with the key grip.

Result

Result

2 CHECK DTC OUTPUT

  1. Delete the DTC
  2. Insert the key into the ignition key cylinder.
  3.  Check that no code is output.

OK: No DTC is output.

3 CHECK TRANSPONDER KEY AMPLIFIER

 CHECK TRANSPONDER KEY AMPLIFIER

  1. Using an oscilloscope or the intelligent tester, check the waveform between the terminals of the I14 amplifier and T6 ECU connector.

    Check that no noise is included in the waveform (an example of noise is shown on the left).

  2.  Check that no noise is included in the waveform (an example of noise is shown on the left).

Result

Result

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

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

  1. Disconnect the T6 ECU and I14 amplifier connectors.
  2.  Measure the resistance according to the value(s) in the table below.

Resistance

Resistance

5 REPLACE TRANSPONDER KEY AMPLIFIER

  1. After replacing the transponder key amplifier with a normally functioning transponder key amplifier, check that the engine starts.

OK: The engine starts

END (TRANSPONDER KEY AMPLIFIER DEFECTIVE)

Unmatched Key Code
DTC B2795 Unmatched Key Code DESCRIPTION This DTC is output when a key with a code that has not been registered in the ECU is inserted into the ignition key cylinder. DTC No. D ...

Engine Immobiliser System Malfunction
DTC B2799 Engine Immobiliser System Malfunction DESCRIPTION This DTC is output when the ECM detects errors in communication between the transponder key ECU and the ECM, or in the communication li ...

Other materials:

On-vehicle inspection
1. INSPECT DRIVE BELT (a) Visually check the drive belt for excessive wear, frayed cords, etc. If any defect is found, replace the drive belt. HINT: Cracks on the rib side of a belt are considered acceptable. Replace the belt if there are any missing ribs. 2. CHECK POWER STEERING FLUID ...

Turbine Speed Sensor Circuit No Signal
DESCRIPTION This sensor detects the rotation speed of the input turbine. By comparing the input turbine speed signal (NT) with the counter gear speed sensor signal (NC), the ECM detects the shift timing of the gears and appropriately controls the engine torque and hydraulic pressure accor ...

Communication Error from VSC to ECM
DTC P1630 Communication Error from VSC to ECM DTC U0122 Lost Communication with Vehicle Dynamics Control Module DESCRIPTION The skid control ECU sends signals such as cruise control cancel demand signals and brake operation demand (from ECM) response signals to the ECM when the dynamic laser ...

В© 2011-2024 Copyright www.tsienna.net