B2796

ENGINE IMMOBILISER: ENGINE IMMOBILISER SYSTEM: B2796: No Communication in Immobiliser System

DTC B2796 - No Communication in Immobiliser System

DTC B2798 - Communication Malfunction No. 2

DESCRIPTION

- DTC B2796 is output when a key is inserted into the ignition key cylinder but no communication occurs between the key and transponder key ECU.
- DTC B2798 is output when a key is inserted into the ignition key cylinder but a communication error occurs between the key and transponder key ECU.





WIRING DIAGRAM





INSPECTION PROCEDURE
HINT: When the transponder key ECU is replaced, reregister the ECU - ECM communication ID Engine Immobiliser System.

PROCEDURE

1. CLEAR DTC
(a) Clear the DTC Engine Immobiliser System.
NEXT -- Continue to next step.
2. CHECK FOR DTC
(a) Check for DTC Engine Immobiliser System.
OK:
DTC B2796 or B2798 is not output.
NG -- READ VALUE USING TECHSTREAM (ENGINE IMMOBILISER SYSTEM)
OK -- USE SIMULATION METHOD TO CHECK
3. READ VALUE USING TECHSTREAM (ENGINE IMMOBILISER SYSTEM)
(a) Use the Data List to check if the engine immobiliser system is functioning properly.
OK:
Unset (key is in ignition key cylinder) appears on the screen.

Immobiliser





NG -- CHECK WHETHER ENGINE STARTS WITH OTHER KEYS
OK -- REPLACE TRANSPONDER KEY ECU
4. CHECK WHETHER ENGINE STARTS WITH OTHER KEYS
(a) Check if the engine starts with an already registered vehicle key.
OK:
Engine starts.
NG -- CHECK HARNESS AND CONNECTOR (TRANSPONDER KEY ECU - TRANSPONDER KEY AMPLIFIER)
OK -- REREGISTER KEY CODE OR REPLACE KEY THAT CANNOT START ENGINE
5. CHECK HARNESS AND CONNECTOR (TRANSPONDER KEY ECU - TRANSPONDER KEY AMPLIFIER)




(a) Disconnect the J26 ECU connector.
(b) Disconnect the J20 amplifier connector.
(c) Measure the resistance according to the value(s) in the table below.
Standard resistance:






NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- Continue to next step.
6. REPLACE TRANSPONDER KEY AMPLIFIER
(a) Temporarily replace the transponder key amplifier with a new or normally functioning one Removal.
NEXT -- Continue to next step.
7. CHECK WHETHER ENGINE STARTS
(a) Check that the engine starts normally.
OK:
Engine starts normally.
NG -- REPLACE TRANSPONDER KEY ECU
OK -- END (TRANSPONDER KEY AMPLIFIER IS DEFECTIVE)