LIN COMMUNICATION SYSTEM, Diagnostic DTC:U1131

DTC Code DTC Name
U1131 Lost Communication with Rear Climate Control Seat ECU LH

DESCRIPTION

This DTC is output when LIN communication between the rear seat climate control ECU LH and rear power seat module switch stops for 10 seconds or more.

DTC Code DTC Detection Condition Trouble Area
U1131 No communication between rear seat climate control ECU LH and rear power seat module switch for 10 seconds or more

  • Rear seat climate control ECU LH

  • Rear power seat module switch

  • Harness or connector

WIRING DIAGRAM

A01GZ44E04

INSPECTION PROCEDURE

Note


  • When using the intelligent tester with the power switch off to troubleshoot:

    Connect the intelligent tester to the vehicle, and turn a courtesy switch on and off at 1.5 second intervals until communication between the tester and vehicle begins.

  • Inspect the fuses for circuits related to this system before performing the following inspection procedure.

Tech Tips

When DTC U0211, U0246, U1130 and U1131 are output simultaneously, perform troubleshooting for "Rear Side Switch Module LIN Communication Malfunction" first Click here.

PROCEDURE


  1. CLEAR DTC


    1. Clear the DTC Click here.


    NEXT

  2. CHECK FOR DTC


    1. Recheck for DTC Click here.

      Result
      Result Proceed to
      DTC U1131 output reoccurs A
      DTC U1131 output does not reoccur B

    B

    USE SIMULATION METHOD TO CHECK Click here

    A

  3. CHECK HARNESS AND CONNECTOR (REAR POWER SEAT SWITCH - SEAT CLIMATE CONTROL ECU)


    1. A01H0MXE07

      Disconnect the z54*1 or S15*2 module switch connector.


      • *1: except 4-Passenger with Ottoman

      • *2: for 4-Passenger with Ottoman

    2. Disconnect the f13*3 or f28*4 ECU connector.


      • *3: w/ Seat Heater System

      • *4: w/ Climate Control Seat System

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


      1. w/ Seat Heater System

        Standard resistance
        except 4-Passenger with Ottoman
        Tester Connection Condition Specified Condition
        z54-12 (MPX) - f13-13 (LIN) Always Below 1 Ω
        z54-12 (MPX) or f13-13 (LIN) - Body ground Always 10 kΩ or higher
        for 4-Passenger with Ottoman
        Tester Connection Condition Specified Condition
        S15-5 (MPX) - f13-13 (LIN) Always Below 1 Ω
        S15-5 (MPX) or f13-13 (LIN) - Body ground Always 10 kΩ or higher
        Standard voltage
        except 4-Passenger with Ottoman
        Tester Connection Switch Condition Specified Condition
        z54-12 (MPX) - f13-13 (LIN) Power switch on (IG) Below 1 V
        for 4-Passenger with Ottoman
        Tester Connection Switch Condition Specified Condition
        S15-5 (MPX) - f13-13 (LIN) Power switch on (IG) Below 1 V

      2. w/ Climate Control Seat System

        Standard resistance
        except 4-Passenger with Ottoman
        Tester Connection Condition Specified Condition
        z54-12 (MPX) - f28-13 (LIN) Always Below 1 Ω
        z54-12 (MPX) or f28-13 (LIN) - Body ground Always 10 kΩ or higher
        for 4-Passenger with Ottoman
        Tester Connection Condition Specified Condition
        S15-5 (MPX) - f28-13 (LIN) Always Below 1 Ω
        S15-5 (MPX) or f28-13 (LIN) - Body ground Always 10 kΩ or higher
        Standard voltage
        except 4-Passenger with Ottoman
        Tester Connection Switch Condition Specified Condition
        z54-12 (MPX) - f28-13 (LIN) Power switch on (IG) Below 1 V
        for 4-Passenger with Ottoman
        Tester Connection Switch Condition Specified Condition
        S15-5 (MPX) - f28-13 (LIN) Power switch on (IG) Below 1 V

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  4. CHECK HARNESS AND CONNECTOR (SEAT CLIMATE CONTROL ECU - BATTERY AND BODY GROUND)


    1. A01GYC4E13

      Disconnect the f13*1 or f28*2 ECU connector.


      • *1: w/ Seat Heater System

      • *2: w/ Climate Control Seat System

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


      1. w/ Seat Heater System

        Standard resistance
        Tester Connection Condition Specified Condition
        f13-12 (GND) - Body ground Always Below 1 Ω
        Standard voltage
        Tester Connection Condition Specified Condition
        f13-1 (IG) - Body ground Power switch off Below 1 V
        f13-1 (IG) - Body ground Power switch on (IG) 11 to 14 V
        f13-2 (SYSB) - Body ground Always 11 to 14 V

      2. w/ Climate Control Seat System

        Standard resistance
        Tester Connection Condition Specified Condition
        f28-12 (GND) - Body ground Always Below 1 Ω
        Standard voltage
        Tester Connection Condition Specified Condition
        f28-1 (IG) - Body ground Power switch off Below 1 V
        f28-1 (IG) - Body ground Power switch on (IG) 11 to 14 V
        f28-2 (SYSB) - Body ground Always 11 to 14 V

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  5. CHECK REAR SEAT CLIMATE CONTROL ECU LH (OPERATION)


    1. Temporarily replace the rear seat climate control ECU LH with a new or normally functioning one.


    2. Clear the DTC Click here.


    NEXT

  6. CHECK FOR DTC


    1. Recheck for DTC Click here.

      Result
      Result Proceed to
      DTC U1131 output does not reoccur A
      DTC U1131 output reoccurs (for 4-Passenger with Ottoman) B
      DTC U1131 output reoccurs (for 5-Passenger with Ottoman) C
      DTC U1131 output reoccurs (for Power Seat) D
      DTC U1131 output reoccurs (for Fixed Seat Type) E

    B

    REPLACE REAR POWER SEAT MODULE SWITCH Click here

    C

    REPLACE REAR POWER SEAT MODULE SWITCH Click here

    D

    REPLACE REAR POWER SEAT MODULE SWITCH Click here

    E

    REPLACE REAR POWER SEAT MODULE SWITCH Click here

    A

    END (REAR SEAT CLIMATE CONTROL ECU LH IS DEFECTIVE)