DTC    B2786    No Response from Steering Lock ECU

for Preparation Click here


DESCRIPTION

This DTC is stored when LIN communication between the certification ECU (smart key ECU assembly) and transmission control ECU assembly stops for 10 seconds or more.

DTC No.
DTC Detection Condition
Trouble Area
B2786
No communication between transmission control ECU assembly and certification ECU (smart key ECU assembly) for 10 seconds or more.
  1. Transmission control ECU assembly
  2. Certification ECU (smart key ECU assembly)
  3. Wire harness or connector
  4. P CON MAIN fuse

WIRING DIAGRAM


B270964E02


INSPECTION PROCEDURE

HINT:
Although "No Response from Steering Lock ECU" is displayed on the intelligent tester, this message is shown if the certification ECU (smart key ECU assembly) cannot communicate with the transmission control ECU assembly.

NOTICE:
  1. Inspect the fuses for circuits related to this system before performing the following inspection procedure.
  2. If the certification ECU (smart key ECU assembly) is replaced, register the key.
  3. If the transmission control ECU assembly is replaced, register the ECU code.
  4. When using the intelligent tester to troubleshoot with the power switch off:
    Connect the intelligent tester to the DLC3, and turn the courtesy switch on and off at 1.5-second intervals until communication between the intelligent tester and vehicle begins.

1.CHECK HARNESS AND CONNECTOR (TRANSMISSION CONTROL ECU ASSEMBLY - BATTERY AND BODY GROUND)

  1. Disconnect the A21 and A22 transmission control ECU assembly connectors.

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

    Standard Resistance:
    Tester Connection
    		Condition
    		Specified Condition
    A22-6 (E01) - Body ground
    		Always
    		Below 1 Ω
    A22-5 (E02) - Body ground
    		Always
    		Below 1 Ω
    A22-1 (E1) - Body ground
    		Always
    		Below 1 Ω

    Standard Voltage:
    Tester Connection
    		Condition
    		Specified Condition
    A21-15 (BATT) - Body ground
    		Power switch off
    		11 to 14 V



NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK


2.CHECK HARNESS AND CONNECTOR (CERTIFICATION ECU - TRANSMISSION CONTROL ECU ASSEMBLY)

  1. Disconnect the H1*1 or H143*2 certification ECU (smart key ECU assembly) connector.

    1. *1: w/ Entry Function
    2. *2: w/o Entry Function

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

    Standard Resistance:
    w/ Entry Function 
    Tester Connection
    		Condition
    		Specified Condition
    H1-29 (LIN) - A22-24 (LIN)
    		Always
    		Below 1 Ω
    H1-29 (LIN) - Body ground
    		Always
    		10 kΩ or higher
    w/o Entry Function 
    Tester Connection
    		Condition
    		Specified Condition
    H143-29 (LIN) - A22-24 (LIN)
    		Always
    		Below 1 Ω
    H143-29 (LIN) - Body ground
    		Always
    		10 kΩ or higher



NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK


3.REPLACE TRANSMISSION CONTROL ECU ASSEMBLY

  1. Replace the transmission control ECU assembly (Click here).


NEXT


4.CHECK DTC OUTPUT

  1. Clear the DTC (Click here).

  1. Recheck for DTCs.

    OK:
    DTC B2786 is not output.



NG
REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)
OK

END (TRANSMISSION CONTROL ECU ASSEMBLY WAS DEFECTIVE)