CAN COMMUNICATION SYSTEM > Certification ECU Communication Stop Mode

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DESCRIPTION


Detection Item
Symptom
Trouble Area
Certification ECU Communication Stop Mode
  1. "Entry & Start/Wireless Tuner" is not displayed on the "Communication Bus Check" screen of the intelligent tester.
  2. Applies to Certification ECU Communication Stop Mode in DTC Combination Table.
  1. Certification ECU branch line or connector
  2. Power source circuit of Certification ECU
  3. Certification ECU (Smart key ECU assembly)

WIRING DIAGRAM


C237145E01


INSPECTION PROCEDURE

NOTICE:
  1. Turn the power switch off before measuring the resistances between CAN main bus lines and between CAN branch lines.
  2. Turn the power switch off before inspecting CAN bus lines for a ground short.
  3. After the power switch is turned off, check that the key reminder warning system and light reminder warning system are not operating.
  4. Before measuring the resistance, leave the vehicle as is for at least 1 minute and do not operate the power 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:
  1. Operating the power 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 (CERTIFICATION ECU BRANCH LINE)

  1. Turn the power switch off.



    C201680E36

  1. Disconnect the certification ECU (smart key ECU assembly) connector.

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

    Standard Resistance:
    Tester Connection
    		Switch Condition
    		Specified Condition
    H1-9 (CANH) - H1-10 (CANL)*1
    H143-9 (CANH) - H143-10 (CANL)*2
    		Power switch off
    		54 to 69 Ω

    *1: w/ Entry function
    *2: w/o Entry function
    Text in Illustration 
    *1
    		w/ Entry function
    *2
    		w/o Entry function
    *a
    		Front view of wire harness connector
    (to Certification ECU)



NG
REPAIR OR REPLACE CAN BRANCH LINE OR CONNECTOR (CERTIFICATION ECU)
OK


2.CHECK HARNESS AND CONNECTOR (POWER SOURCE CIRCUIT)


    C201680E37

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

    Standard Resistance:
    Tester Connection
    		Condition
    		Specified Condition
    H1-15 (E) - Body ground*1
    H143-15 (E) - Body ground*2
    		Always
    		Below 1 Ω

    *1: w/ Entry function
    *2: w/o Entry function

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

    Standard Voltage:
    Tester Connection
    		Switch Condition
    		Specified Condition
    H1-1 (+B) - Body ground*1
    H143-1 (+B) - Body ground*2
    		Power switch off
    		11 to 14 V
    H1-16 (IG) - Body ground*1
    H143-16 (IG) - Body ground*2
    		Power switch on (IG)
    		11 to 14 V

    *1: w/ Entry function
    *2: w/o Entry function
    Text in Illustration 
    *1
    		w/ Entry function
    *2
    		w/o Entry function
    *a
    		Front view of wire harness connector
    (to Certification ECU)



NG
REPAIR OR REPLACE HARNESS OR CONNECTOR (POWER SOURCE CIRCUIT)
OK

REPLACE SMART KEY ECU ASSEMBLY (CERTIFICATION ECU)