Can Communication System Main Body Ecu Communication Stop Mode

Power Source Network. Corolla. Zre142 Aze141
Networking. Corolla. Zre142 Aze141

DESCRIPTION

WIRING DIAGRAM

INSPECTION PROCEDURE

CHECK CAN BUS LINE FOR DISCONNECTION (MAIN BODY ECU BRANCH WIRE)

CHECK HARNESS AND CONNECTOR (BECU, IG, GND1)

CAN COMMUNICATION SYSTEM - Main Body ECU Communication Stop Mode


DESCRIPTION


Detection Item
Symptom
Trouble Area
Main Body ECU Communication Stop Mode
  1. "Main body" is not displayed on the "CAN Bus Check" screen of the Techstream
  2. Applies to "Main Body ECU Communication Stop Mode" in "DTC Combination Table"
  1. Power source circuit of the main body ECU
  2. Main body ECU branch wire or connector
  3. Main body ECU

WIRING DIAGRAM


Corolla. Zre142 Aze141.Networking.Lin Communication System.Can Communication System Main Body Ecu Communication Stop Mode


Corolla. Zre142 Aze141.Networking.Lin Communication System.Can Communication System Main Body Ecu Communication Stop Mode


INSPECTION PROCEDURE

NOTICE:
  1. Turn the ignition switch off before measuring the resistance between main CAN bus wires and CAN Bus branch wires.
  2. After the ignition switch is turned off, check that the key reminder warning system and light reminder warning system are not operating.
  3. 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.
HINT:
  1. 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.
  2. 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.
1.CHECK CAN BUS LINE FOR DISCONNECTION (MAIN BODY ECU BRANCH WIRE)


    Corolla. Zre142 Aze141.Networking.Lin Communication System.Can Communication System Main Body Ecu Communication Stop Mode

  1. Turn the ignition switch off.

    Text in Illustration
    *A
    		w/ Smart Key System
    *B
    		w/o Smart Key System
    *a
    		Front view of wire harness connector
    (to Main Body ECU)

  1. Disconnect the main body ECU connector.

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

    Standard Resistance:
    w/ Smart Key System:
    Tester Connection
    		Switch Condition
    		Specified Condition
    E52-15 (CANH) - E52-16 (CANL)
    		Ignition switch off
    		54 to 69 Ω
    w/o Smart Key System:
    Tester Connection
    		Switch Condition
    		Specified Condition
    E61-23 (CANH) - E61-22 (CANL)
    		Ignition switch off
    		54 to 69 Ω


NG
REPAIR OR REPLACE CAN BUS BRANCH WIRE OR CONNECTOR (MAIN BODY ECU BRANCH WIRE)
OK


2.CHECK HARNESS AND CONNECTOR (BECU, IG, GND1)


    Corolla. Zre142 Aze141.Networking.Lin Communication System.Can Communication System Main Body Ecu Communication Stop Mode

  1. Disconnect the instrument panel junction block connectors.

    Text in Illustration
    *a
    		Front view of wire harness connector
    (to Instrument Panel Junction Block)

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

    Standard Resistance:
    Tester Connection
    		Condition
    		Specified Condition
    2E-17 (GND1) - Body ground
    		Always
    		Below 1 Ω

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

    Standard Voltage:
    Tester Connection
    		Condition
    		Specified Condition
    2B-30 (BECU) - Body ground
    		Always
    		10 to 14 V


NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK

REPLACE INSTRUMENT PANEL JUNCTION BLOCK (MAIN BODY ECU)