Toyota CH-R Service Manual: ID BOX EEPROM Malfunction (B2790)

Toyota CH-R Service Manual / Theft Deterrent / Keyless Entry / Immobiliser System(w/ Smart Key System) / ID BOX EEPROM Malfunction (B2790)

DESCRIPTION

When an internal malfunction occurs in the ID code box (immobiliser code ECU), the certification ECU (smart key ECU assembly) stores this DTC.

DTC No.

Detection Item

DTC Detection Condition

Trouble Area

Note

B2790

ID BOX EEPROM Malfunction

An internal malfunction occurs in the ID code box (immobiliser code ECU) (EEPROM access malfunction). (1 trip detection logic*)
  • ID code box (immobiliser code ECU)
  • Certification ECU (smart key ECU assembly)

DTC output confirmation operation:

  • An immobiliser set/unset operation is performed (the engine switch is turned off or on (IG) while the key is being carried).
  • *: 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 running: Engine cannot be started next time
  • Engine stopped: Engine cannot be started

-
Related Data List and Active Test

DTC No.

Data List and Active Test

B2790

-

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 certification ECU (smart key ECU assembly) 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."

PROCEDURE

1.

REPLACE ID CODE BOX (IMMOBILISER CODE ECU)

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

Click here

NEXT

2.

CLEAR DTC

(a) Clear the DTCs.

Click here

Body Electrical > Smart Key > Clear DTCs
NEXT

3.

REGISTER RECOGNITION CODE

(a) Register the recognition code to the ECUs.

Click here

NEXT

4.

REGISTER ECU COMMUNICATION ID

(a) Register the ECU communication ID codes.

Click here

NEXT

5.

CHECK FOR DTC

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

(b) Check for DTCs.

Click here

Body Electrical > Smart Key > Trouble Codes

OK:

DTC B2790 is not output.

OK

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

REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)

    Engine Starter Communication Malfunction (B2779)
    DESCRIPTION If the remote engine start ECU does not respond to the certification ECU (smart key ECU assembly) or the remote engine start ID is not registered, this DTC is stored. HINT: Registrati ...

    Short to GND in Immobiliser System Power Source Circuit (B278A)
    DESCRIPTION When there is a short to GND in the power supply for the transponder key amplifier of the engine switch, the certification ECU (smart key ECU assembly) stores this DTC. DT ...

    Other materials:

    Toyota CH-R Service Manual > Lighting (ext): Automatic High Beam Main Switch
    Components COMPONENTS ILLUSTRATION *1 AUTO HIGH BEAM SWITCH *2 INSTRUMENT CLUSTER FINISH PANEL SUB-ASSEMBLY Removal REMOVAL PROCEDURE 1. REMOVE INSTRUMENT CLUSTER FINISH PANEL SUB-ASSEMBLY Click here 2. REMOVE AUTO HIGH BEAM ...

    Toyota CH-R Service Manual > Vacuum Pump: Reassembly
    REASSEMBLY PROCEDURE 1. INSTALL VACUUM PUMP VANE (a) Apply engine oil to the vacuum pump vane and 2 vacuum pump vane caps. (b) Install the vacuum pump vane caps to the vacuum pump vane. NOTICE: When reusing the vacuum pump vane and vacuum pump vane caps, install them in the ...

    Toyota C-HR (AX20) 2023-2026 Owner's Manual

    Toyota CH-R Owners Manual

    Toyota CH-R Service Manual

    © 2017-2026 Copyright www.tochr.net
    0.0075