Toyota Tundra Service Manual: No Communication in Immobiliser System (B2796)

Toyota Tundra Service Manual / Vehicle Interior / Engine Immobiliser / Engine Immobiliser System (w/o Smart Key System) / 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 Transponder key coil Transponder key ECU assembly	Insert the key into the ignition key cylinder.

*: 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 cannot be started	-

Related Data List and Active Test

DTC No.	Data List and Active Test
B2796	Response

WIRING DIAGRAM

CAUTION / NOTICE / HINT

NOTICE:

If the transponder key ECU assembly or key is replaced, refer to Registration.
Click here
After repair, confirm that no DTCs are output by performing "DTC Output Confirmation Operation".

PROCEDURE

CLEAR DTC

(a) Clear the DTCs.

Click here

2.	CHECK FOR DTC

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

Click here

HINT:

Before checking for DTCs, perform the "DTC Output Confirmation Operation" procedure.
If DTC B2796 is stored, check for DTCs with the next key after clearing the DTCs.

OK:

DTC 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

USE SIMULATION METHOD TO CHECK

GO TO STEP 8

3.	REPLACE TRANSPONDER KEY ECU ASSEMBLY

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

Click here

4.	REGISTER KEY

(a) Register the key.

Click here

5.	REGISTER ECU COMMUNICATION ID

(a) Register the ECU communication ID.

Click here

CLEAR DTC

(a) Clear the DTCs.

Click here

7.	CHECK FOR DTC

(a) Check for DTCs.

Click here

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

END (TRANSPONDER KEY ECU ASSEMBLY WAS DEFECTIVE)

REPLACE KEY THAT DTC IS OUTPUT

8.	REPLACE KEY

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

Click here

CLEAR DTC

(a) Clear the DTCs.

Click here

10.	CHECK FOR DTC

(a) Check for DTCs.

Click here

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

END (KEY WAS DEFECTIVE)

REPLACE TRANSPONDER KEY ECU ASSEMBLY

Unmatched Key Code (B2795)

Engine Immobiliser System Malfunction (B2799)

See More:

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