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

CLEAR DTC

(a) Clear the DTCs.

Click here

Body Electrical > Smart Key > Clear DTCs

3.	REGISTER RECOGNITION CODE

(a) Register the recognition code to the ECUs.

Click here

4.	REGISTER ECU COMMUNICATION ID

(a) Register the ECU communication ID codes.

Click here

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.

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

REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)

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

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