CAN COMMUNICATION SYSTEM ECM Communication Stop Mode

DESCRIPTION

Detection Item Symptom Trouble Area
ECM Communication Stop Mode

  • "Engine" is not displayed on "Communication Bus Check" screen of intelligent tester

  • Applies to "ECM Communication Stop Mode" in "DTC COMBINATION TABLE"

  • Power source circuit of ECM

  • ECM

WIRING DIAGRAM

A017E3GE02
A017DZOE01

INSPECTION PROCEDURE

Note


  • Turn the ignition switch off before measuring the resistances of CAN bus main wires and CAN bus branch wires.

  • After the ignition 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 1 minute and do not operate the ignition switch, any other switches, or the doors. If any doors need to be opened in order to check the connectors, open the doors and leave them open.

Tech Tips


  • Operating the ignition 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 will help determine the cause of the malfunction.

PROCEDURE


  1. CHECK FOR OPEN IN CAN NO. 1 BUS MAIN WIRE (ECM MAIN WIRE)


    1. Turn the ignition switch off.

    2. Disconnect the ECM connector.

    3. A017EELE04

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

      Standard resistance
      Tester Connection Condition Specified Condition
      D32-33 (CANH) - D32-34 (CANL) Ignition switch off 108 to 132 Ω

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  2. CHECK WIRE HARNESS (POWER SOURCE CIRCUIT)


    1. Check the ECM power source circuit Click here.


    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

    REPLACE ECM Click here