Up to 08/2009

NETWORKING: CAN COMMUNICATION SYSTEM: ECM Communication Stop Mode
- ECM Communication Stop Mode

DESCRIPTION





WIRING DIAGRAM





INSPECTION PROCEDURE

NOTICE:
* Turn the engine switch off before measuring the resistances between CAN bus main wires and between CAN bus branch wires.
* Turn the engine switch off before inspecting CAN bus wires for a ground short.
* After the engine switch is turned off, check that the key reminder warning system and light reminder warning system are not operating.
* Before measuring the resistance, leave the vehicle as is for at least 1minute and do not operate the engine switch, any other switches or the doors. If any doors need to be opened in order to check connectors, open the doors and leave them open.
HINT
* Operating the engine switch, any other switches or a door triggers related ECU and sensor communication on the CAN. This communication will cause the resistance value to change.
* Even after DTCs are cleared, if a DTC is stored again after driving the vehicle for a while, the malfunction may be occurring due to vibration of the vehicle. In such a case, wiggling the ECUs or wire harness while performing the inspection below may help determine the cause of the malfunction.
PROCEDURE

1. CHECK CAN BUS WIRE FOR DISCONNECTION (ECM MAIN WIRE)

(a) Turn the engine switch off.

(b) Disconnect the ECM connector.





Text in Illustration





(c) Measure the resistance according to the value(s) in the table below.

Standard Resistance:





NG -- REPAIR OR REPLACE CAN BUS MAIN WIRE OR CONNECTOR (ECM MAIN WIRE)
OK -- Continue to next step.

2. CHECK ECM POWER SOURCE CIRCUIT

(a) Check the ECM power source circuit ECM Power Source Circuit.

OK:

The ECM power source circuit is normal.

HINT
If there is no abnormality in the ECM power source circuit, replace the ECM.

NG -- REPAIR OR REPLACE ECM POWER SOURCE CIRCUIT

OK -- REPLACE ECM Removal