Engine Immobiliser System (w/o Smart Key System)

ENGINE IMMOBILISER: ENGINE IMMOBILISER SYSTEM (w/o Smart Key System): B2797: Communication Malfunction No. 1

DTC B2797 - Communication Malfunction No. 1

DESCRIPTION

This DTC is output when a communication error occurs between the key slot and transponder key ECU. A possible reason for the communication error is that noise is occurring on the communication line. Following the inspection procedure below.






WIRING DIAGRAM





INSPECTION PROCEDURE

PROCEDURE

1. CHECK TRANSPONDER KEY ECU




(a) Using an oscilloscope or the Techstream, check for noise in the waveform between the terminals of the K3 key slot connector and T5 ECU connector.
OK:
No noise is present (see illustration).






NG -- FIND CAUSE OF NOISE AND REMOVE IT
OK -- Continue to next step.

2. CHECK WIRE HARNESS (TRANSPONDER KEY ECU - KEY SLOT)




(a) Disconnect the T5 ECU connector.
(b) Disconnect the K3 key slot connector.
(c) Measure the resistance of the wire harness side connectors.
Standard resistance:






NG -- REPAIR OR REPLACE HARNESS AND CONNECTOR
OK -- Continue to next step.

3. CHECK KEY SLOT (OPERATION)
(a) Temporarily replace the key slot with a new or normally functioning one.
(b) Check that the power switch can be turned ON (ACC and IG) and the hybrid control system can be started.
OK:
Power switch can be turned ON (ACC and IG) and hybrid control system can be turned.
NG -- REPLACE TRANSPONDER KEY ECU
OK -- END (KEY SLOT IS DEFECTIVE)