Toyota CH-R Service Manual: No Communication in Immobiliser System (B2796)

DESCRIPTION

This DTC 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 No.	Detection Item	DTC Detection Condition	Trouble Area	Note
B2796	No Communication in Immobiliser System	The key ID code cannot be transmitted to the transponder key ECU assembly (1 trip detection logic*).	Key Wire harness or connector Transponder key coil Transponder key ECU assembly	Insert the key into the ignition key cylinder.

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
B2796	-

WIRING DIAGRAM

CAUTION / NOTICE / HINT

PROCEDURE

1.

CLEAR DTC

(a) Clear the DTCs.

Body Electrical > Immobiliser > Clear DTCs

NEXT

2.	CHECK FOR DTC

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

Body Electrical > Immobiliser > Trouble Codes

HINT:

Before checking for DTCs, perform the "DTC Output Confirmation Operation" procedure.

OK:

B2796 is not output.

Result	Proceed to
B2796 is not output	A
DTC B2796 is output for all of the keys	B
DTC B2796 is output for any of the keys	C

A

USE SIMULATION METHOD TO CHECK

C

GO TO STEP 6

B

3.	REPLACE TRANSPONDER KEY ECU ASSEMBLY

(a) Replace the transponder key ECU assembly with a new one.

Click here

HINT:

Refer to Registration.

Click here

NOTICE:

Key ID code registration is necessary when replacing the transponder key ECU assembly.

Click here

NEXT

4.

CLEAR DTC

(a) Clear the DTCs.

Body Electrical > Immobiliser > Clear DTCs

NEXT

5.	CHECK FOR DTC

(a) Check for DTCs.

Body Electrical > Immobiliser > Trouble Codes

HINT:

Before checking for DTCs, perform the "DTC Output Confirmation Operation" procedure.

OK:

DTC B2796 is not output.

Result	Proceed to
B2796 is not output	A
B2796 is output	B

A

END (TRANSPONDER KEY ECU ASSEMBLY WAS DEFECTIVE)

B

REPLACE KEY THAT DTC IS OUTPUT

6.	REPLACE KEY

(a) Replace the key for which the DTC was stored.

NOTICE:

Key ID code registration is necessary when replacing the key.

Click here

NEXT

7.

CLEAR DTC

(a) Clear the DTCs.

Body Electrical > Immobiliser > Clear DTCs

NEXT

8.	CHECK FOR DTC

(a) Check for DTCs.

Body Electrical > Immobiliser > Trouble Codes

HINT:

Before checking for DTCs, perform the "DTC Output Confirmation Operation" procedure.

OK:

DTC B2796 is not output.

Result	Proceed to
B2796 is not output	A
B2796 is output	B

A

END (KEY WAS DEFECTIVE)

B

REPLACE TRANSPONDER KEY ECU ASSEMBLY