Description

CHART 1: NO COMMUNICATION WITH THE ECM

Diagnosis Procedure

1.INSPECTION START

Ensure that CONSULT-III is not causing the malfunction by trying to establish dialogue with an ECM on another vehicle. If the CONSULT-III is not at malfunction, and dialogue cannot be established with any other ECM on the same vehicle, the cause could be a suspected ECM interfering on the CAN communication line.

Check the voltage of the battery and carry out the operations necessary to obtain a voltage which is to specification (9.5 V < U battery < 17.5 V).

>> GO TO 2.

2.CHECK CAN COMMUNICATION

Perform trouble diagnosis on the CAN communication line using CONSULT-III. Refer to LAN-31, "CAN COMMUNICATION SYSTEM : CAN Communication Signal Chart".

Is the inspection result normal? YES >> GO TO 3.

NO >> Repair or replace harness or connector.

3.CHECK ECM GROUND

Check the ECM earth (ground).

Is the inspection result normal? YES >> GO TO 4.

NO >> Repair or replace ground connection.

4.CHECK ECM POWER SUPPLY AND GROUND CIRCUIT

Check ECM power supply and ground circuit. Refer to EC-885, "Diagnosis Procedure".

Is the inspection result normal? YES >> GO TO 5.

NO >> Repair or replace harness or connector.

5.CHECK DATA LINK CONNECTOR CIRCUIT

Check for the presence of 12 V on terminal 16 with ignition switch OFF, 12 V on terminal 8 with ignition switch ON and an earth (ground) on terminals 4 and 5 of the data link connector.

Repair if necessary.

Is the inspection result normal? YES >> INSPECTION END

NO >> Repair or replace harness or connector.