B2797

THEFT DETERRENT / KEYLESS ENTRY: ENGINE IMMOBILISER SYSTEM (w/o Smart Key System): B2797: Communication Malfunction No. 1
B2797 - Communication Malfunction No. 1

DESCRIPTION

This DTC is stored when a communication error occurs between the transponder key amplifier and transponder key ECU assembly. Some possible reasons for the communication error are: 1) 2 or more ignition keys are positioned too close together, or 2) noise is occurring in the communication line.





WIRING DIAGRAM





INSPECTION PROCEDURE

NOTICE:
When the transponder key ECU assembly is replaced, refer to Registration Engine Immobilizer System (w/o Smart Key System).

PROCEDURE

1. CHECK KEY

(a) Check whether the ignition key being used is near other ignition keys, as shown in the illustration. Also, check whether a key ring is in contact with the key grip.





Result





B -- CHECK HARNESS AND CONNECTOR (TRANSPONDER KEY ECU - TRANSPONDER KEY AMPLIFIER)
A -- Continue to next step.

2. CHECK FOR DTC

(a) Separate the keys from each other or remove the key ring.

(b) Clear the DTCs Engine Immobilizer System (w/o Smart Key System).

(c) Insert a key into the ignition key cylinder, and then remove it. Repeat this for all the other keys.

(d) Check that no DTC is output Engine Immobilizer System (w/o Smart Key System).

OK:

DTC B2797 is not output.

NG -- CHECK HARNESS AND CONNECTOR (TRANSPONDER KEY ECU - TRANSPONDER KEY AMPLIFIER)

OK -- END

3. CHECK HARNESS AND CONNECTOR (TRANSPONDER KEY ECU - TRANSPONDER KEY AMPLIFIER)

(a) Disconnect the F34 ECU connector.

(b) Disconnect the F17 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.

4. CHECK TRANSPONDER KEY ECU ASSEMBLY (NOISE)

(a) Using an oscilloscope, check for noise in the waveform between the terminals of the F17 amplifier connector and F34 ECU connector.





Measurement Condition





OK:

No noise is present.

Text in Illustration





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

5. REPLACE TRANSPONDER KEY AMPLIFIER

(a) Temporarily replace the transponder key amplifier with a new or normally functioning one Removal.

NEXT -- Continue to next step.

6. CHECK WHETHER ENGINE STARTS

(a) Check that the engine starts normally.

OK:

Engine starts.

NG -- REPLACE TRANSPONDER KEY ECU ASSEMBLY Removal

OK -- END (TRANSPONDER KEY AMPLIFIER IS DEFECTIVE)