Toyota CH-R Service Manual: Engine Immobiliser System Malfunction (B2799)

Toyota CH-R Service Manual / Theft Deterrent / Keyless Entry / Immobiliser System(w/ Smart Key System) / Engine Immobiliser System Malfunction (B2799)

DESCRIPTION

If there is a communication malfunction between the ECM and ID code box (immobiliser code ECU), or when the communication ID codes do not match, the ECM stores this DTC.

DTC No.

Detection Item

DTC Detection Condition

Trouble Area

Note

B2799

Engine Immobiliser System Malfunction

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

  • A malfunction in the communication between the ECM and ID code box (immobiliser code ECU).
  • A malfunction in the communication lines between the ECM and ID code box (immobiliser code ECU).
  • A matching communication code cannot be verified during communication between the ECM and ID code box (immobiliser code ECU).
  • ID code box (immobiliser code ECU)
  • ECM
  • Wire harness or connector

DTC output confirmation operation (Perform either of the following):

  • Start the engine and wait for 10 seconds. If there is a malfunction, the engine will stop (communication begins within 3 seconds of the engine start operation being performed, and DTCs are stored after 6 seconds).
  • Connect the cable to the negative (-) battery terminal, start the engine and wait for 10 seconds (communication begins within 3 seconds of the engine switch being turned on (IG), and DTCs are stored after 6 seconds).
  • *: Only output while a malfunction is present.
DTC Detection Conditions
 

Vehicle Condition

Pattern 1

Pattern 2

Pattern 3

Diagnosis Condition

Engine start operation.

○

○

○

Malfunction Status

A malfunction in the communication between the ECM and ID code box (immobiliser code ECU).

○

-

-

A malfunction in the communication lines between the ECM and ID code box (immobiliser code ECU).

-

○

-

A matching communication code cannot be verified during communication between the ECM and ID code box (immobiliser code ECU).

-

-

○

Detection Time

-

-

  

Number of Trips

1 trip

1 trip

1 trip

HINT:

DTC will be output when conditions for either of the patterns in the table above are met.

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 No.

Data List and Active Test

B2799

-

WIRING DIAGRAM

CAUTION / NOTICE / HINT

NOTICE:

  • When using the Techstream with the engine switch off, connect the Techstream to the DLC3 and turn a courtesy light switch on and off at intervals of 1.5 seconds or less until communication between the Techstream and the vehicle begins. Then select the vehicle type under manual mode and enter the following menus: Body Electrical / Smart Key. While using the Techstream, periodically turn a courtesy light switch on and off at intervals of 1.5 seconds or less to maintain communication between the Techstream and the vehicle.
  • Before replacing the ECM or ID code box (immobiliser code ECU), refer to Registration.

    Click here

  • After performing repairs, confirm that no DTCs are output by performing "DTC Output Confirmation Operation".

HINT:

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

PROCEDURE

1.

REGISTER ECU COMMUNICATION ID

(a) Register the ECU communication ID code.

Click here

NEXT

2.

CLEAR DTC

(a) Clear the DTCs.

Click here

Powertrain > Engine and ECT > Clear DTCs
NEXT

3.

CHECK FOR DTC

(a) Perform "DTC Output Confirmation Operation" procedure.

(b) Check for DTCs.

Click here

Powertrain > Engine and ECT > Trouble Codes

OK:

B2799 is not output.

OK

END (COMMUNICATION ID REGISTRATION WAS DEFECTIVE)
NG

4.

CHECK HARNESS AND CONNECTOR (ID CODE BOX (IMMOBILISER CODE ECU) - ECM)

(a) Disconnect the F21 ID code box (immobiliser code ECU) connector.

(b) Disconnect the A38 ECM connector.

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

F21-4 (EFIO) - A38-28 (IMI)

Always

Below 1 Ω

F21-3 (EFII) - A38-45 (IMO)

Always

Below 1 Ω

F21-4 (EFIO) or A38-28 (IMI) - Body ground

Always

10 kΩ or higher

F21-3 (EFII) or A38-45 (IMO) - Body ground

Always

10 kΩ or higher
NG

REPAIR OR REPLACE HARNESS OR CONNECTOR
OK

5.

REPLACE ID CODE BOX (IMMOBILISER CODE ECU)

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

Click here

NEXT

6.

REGISTER RECOGNITION CODE

(a) Register the recognition codes in the ECUs.

Click here

NEXT

7.

REGISTER ECU COMMUNICATION ID

(a) Register the ECU communication ID.

Click here

NEXT

8.

CHECK WHETHER ENGINE STARTS

(a) Check that the engine starts.

OK:

Engine starts normally.

NG

REPLACE ECM

OK

9.

CLEAR DTC

(a) Clear the DTCs.

Click here

Powertrain > Engine and ECT > Clear DTCs
NEXT

10.

CHECK FOR DTC

(a) Perform "DTC Output Confirmation Operation" procedure.

(b) Check for DTCs.

Click here

Powertrain > Engine and ECT > Trouble Codes

OK:

B2799 is not output.

OK

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

REPLACE ECM

    Theft Deterrent System Presence Detection (B279C)
    DESCRIPTION If an ECM that is incompatible with the immobiliser system is installed, the ECM will store this DTC. DTC No. Detection Item DTC Detection Condition ...

    Immobiliser System does not Operate Properly
    DESCRIPTION The immobiliser system compares the ID code that is registered to the certification ECU (smart key ECU assembly) with the ID code of the transponder chip that is embedded in the elect ...

    Other materials:

    Toyota CH-R Owners Manual > Specifications: Fuel information
    You must only use unleaded gasoline. Select octane rating 87 (Research Octane Number 91) or higher. Use of unleaded gasoline with an octane rating lower than 87 may result in engine knocking. Persistent knocking can lead to engine damage. At minimum, the gasoline you use should meet the spe ...

    Toyota CH-R Service Manual > General Maintenance: Under Hood
    UNDER HOOD GENERAL NOTES Maintenance requirements vary depending on country. Check the maintenance schedule in the owner's manual. Following the maintenance schedule is mandatory. Determine the appropriate time to service the vehicle using either miles driven or time (mo ...

    Toyota CH-R Owners Manual

    Toyota CH-R Service Manual

    © 2017-2025 Copyright www.tochr.net
    0.0136