CAN COMMUNICATION SYSTEM > Engine Stop and Start ECU Communication Stop Mode

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DESCRIPTION


Detection Item
Symptom
Trouble Area
Engine Stop and Start ECU Communication Stop Mode
  1. "Stop and Go" is not displayed on "Communication Bus Check" screen of intelligent tester
  2. Applies to "Engine Stop and Start ECU Communication Stop Mode" in "DTC combination table"
  1. Power source circuit engine stop and start ECU
  2. Engine stop and start ECU branch wire and connector
  3. Engine stop and start ECU

WIRING DIAGRAM


E195022E01


INSPECTION PROCEDURE

NOTICE:
  1. Turn the ignition switch off before measuring the resistances of CAN main wires and CAN 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.
  4. Inspect the fuses for circuits related to this system before performing the following inspection procedure.

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 will help determine the cause of the malfunction.

1.CHECK CAN BUS LINE FOR DISCONNECTION (ENGINE STOP AND START ECU BRANCH WIRE)


    E191432E03

  1. Disconnect the D78 engine stop and start ECU connector.

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

    Standard Resistance:
    Tester Connection
    		Switch Condition
    		Specified Condition
    D78-16 (CANH) - D78-17 (CANL)
    		Ignition switch off
    		54 to 69 Ω

    Text in Illustration 
    *1
    		Front view of wire harness connector
    (to Engine Stop and Start ECU)



NG
REPAIR OR REPLACE CAN BRANCH WIRE CONNECTED TO ENGINE STOP AND START ECU (CANH, CANL)
OK


2.CHECK WIRE HARNESS (ENGINE STOP AND START ECU - BATTERY AND BODY GROUND)


    E191205E02

  1. Disconnect the D78 and D79 engine stop and start ECU connector.

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

      Standard Resistance:
      Tester Connection
      		Condition
      		Specified Condition
      D78-1 (EC) - Body ground
      		Always
      		Below 1 Ω
      D78-6 (E1) - Body ground
      		Always
      		Below 1 Ω

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

      Standard Voltage:
      Tester Connection
      		Switch Condition
      		Specified Condition
      D79-5 (BATT) - Body ground
      		Always
      		11 to 14 V
      D79-6 (+B) - Body ground
      		Ignition switch ON
      		11 to 14 V
      D78-19 (IGSW) - Body ground
      		Ignition switch ON
      		11 to 14 V

      Text in Illustration 
      *1
      		Front view of wire harness connector
      (to Engine Stop and Start ECU)



NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK

REPLACE ENGINE STOP AND START ECU (Click here)