CAN COMMUNICATION SYSTEM > Power Steering ECU Communication Stop Mode

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DESCRIPTION


Detection Item
Symptom
Trouble Area
Power Steering ECU Communication Stop Mode
Either condition is met:
  1. "EPS" is not displayed on "Bus Check".
  2. "Power Steering ECU Communication Stop Mode" in "DTC Combination Table" applies.
  1. Power source or inside power steering ECU
  2. Power steering ECU branch wire or connector
  3. Power steering ECU

WIRING DIAGRAM


C129194E05


INSPECTION PROCEDURE

NOTICE:
  1. Turn the ignition switch off before measuring the resistance of the main wire and the branch wire.
  2. After the ignition switch is turned off, check that the key reminder warning system and light reminder buzzer are not in operation.
  3. Before measuring the resistance, leave the vehicle for at least 1 minute and do not operate the ignition switch, any switches or doors. If doors need to be opened in order to check connectors, open the doors and leave them open.

HINT:
Operating the ignition switch, any switches or any doors triggers related ECU and sensor communication with the CAN, which causes resistance variation.
1.DISCONNECT CABLE FROM NEGATIVE BATTERY TERMINAL

  1. Disconnect the cable from the negative (-) battery terminal before measuring the resistance of the main wire and the branch wire.

    CAUTION:
    Wait at least 90 seconds after disconnecting the cable from the negative (-) battery terminal to disable the SRS system.

    NOTICE:
    1. w/ Navigation System (for HDD):
      After the ignition switch is turned off, the HDD navigation system requires approximately a minute to record various types of memory and settings. As a result, after turning the ignition switch off, wait a minute or more before disconnecting the cable from the negative (-) battery terminal.
    2. When disconnecting the cable, some systems need to be initialized after the cable is reconnected.

NEXT


2.CHECK CAN BUS LINE FOR DISCONNECTION (POWER STEERING ECU BRANCH WIRE)


    C128052E04

  1. Disconnect the E21 power steering ECU connector.

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

    Standard Resistance:
    Tester Connection
    		Switch Condition
    		Specified Condition
    E21-2 (CANH) - E21-8 (CANL)
    		Ignition switch off
    		54 to 69 Ω


NG
REPAIR OR REPLACE POWER STEERING ECU BRANCH WIRE OR CONNECTOR (CANH, CANL)
OK


3.CHECK HARNESS AND CONNECTOR (POWER STEERING ECU - BATTERY AND BODY GROUND)

  1. Connect the cable to the negative (-) battery terminal.

    NOTICE:
    When disconnecting the cable, some systems need to be initialized after the cable is reconnected.


    C128054E02

  1. Disconnect the A2 and E21 power steering ECU connectors.

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

    Standard Resistance:
    Tester Connection
    		Condition
    		Specified Condition
    A2-2 (PGND) - Body ground
    		Always
    		Below 1 Ω

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

    Standard Voltage:
    Tester Connection
    		Switch Condition
    		Specified Condition
    A2-1 (PIG) - Body ground
    		Always
    		11 to 14 V
    E21-5 (IG) - Body ground
    		Ignition switch on (IG)
    		11 to 14 V


NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK

REPLACE POWER STEERING ECU