STOP AND START SYSTEM(for 2WW), Diagnostic DTC:U0100,U0121,U0126,U0131,U0140,U0151,U0155 and U0164

DTC Code DTC Name
U0100 Lost Communication with ECM / PCM "A"
U0121 Lost Communication with Anti-lock Brake System (ABS) Control Module
U0126 Lost Communication With Steering Angle Sensor Module
U0131 Lost Communication with Power Steering Control Module
U0140 Lost Communication with J/B ECU
U0151 Lost Communication with SRS Airbag ECU
U0155 Lost Communication with Instrument Panel Cluster Control Module (Combination Meter)
U0164 Lost Communication with HVAC Control Module

DESCRIPTION

The engine stop and start ECU communicates with the SFI system, vehicle stability control system, power steering system, air conditioning system, airbag system, meter / gauge system and main body ECU (multiplex network body ECU) via CAN communication.

If there is a communication error between the engine stop and start ECU and any of the systems, the engine stop and start ECU stores DTCs and illuminates the stop and start cancel indicator light except when there is a communication error with the meter/gauge system.

Tip:

  • When there is an open in the output side of the backup boost converter (built into the engine stop and start ECU), power to the system with the open is cut off. The engine stop and start ECU stores CAN communication DTCs for the system with the open and stop and start system DTC P323B.

  • When the backup boost converter (built into the engine stop and start ECU) detects overcurrent in any of the circuits it supplies power to, it shuts off the circuit. The engine stop and start ECU stores CAN communication DTCs for the system which circuit was shut off and stores stop and start system DTC B22C0.

    e.g.: When the backup boost converter (built into the engine stop and start ECU) detects overcurrent in the power source circuit of the power steering system and cuts off power supply, the engine stop and start ECU stores DTCs U0131 and B22C0.

DTC No.

Detection Item

DTC Detection Condition

Trouble Area

Warning Indicate

Memory

U0100

Lost Communication with ECM / PCM "A"

No communication between the engine stop and start ECU and ECM for 0.76 seconds.

  • Wire harness or connector

  • Engine stop and start ECU

  • ECM

Blinks

DTC stored

U0121

Lost Communication with Anti-lock Brake System (ABS) Control Module

No communication between the engine stop and start ECU and brake actuator assembly for 2.22 seconds.

  • Wire harness or connector

  • Engine stop and start ECU

  • Brake actuator assembly

Blinks

DTC stored

U0126

Lost Communication With Steering Angle Sensor Module

No communication between the engine stop and start ECU and the spiral with sensor cable sub-assembly for 0.72 seconds.

  • Wire harness or connector

  • Engine stop and start ECU

  • Spiral with sensor cable sub-assembly

Blinks

DTC stored

U0131

Lost Communication with Power Steering Control Module

No communication between the engine stop and start ECU and the power steering ECU assembly for 0.8 seconds.

  • Wire harness or connector

  • Engine stop and start ECU

  • Power steering ECU assembly

Blinks

DTC stored

U0140

Lost Communication with J/B ECU

No communication between the engine stop and start ECU and the main body ECU (multiplex network body ECU) for 3.6 seconds.

  • Wire harness or connector

  • Engine stop and start ECU

  • Main body ECU (multiplex network body ECU)

Blinks

DTC stored

U0151

Lost Communication with SRS Airbag ECU

No communication between the engine stop and start ECU and airbag sensor assembly for 10.6 seconds.

  • Wire harness or connector

  • Engine stop and start ECU

  • Center airbag sensor assembly

Blinks

DTC stored

U0155

Lost Communication with Instrument Panel Cluster Control Module (Combination Meter)

No communication between the engine stop and start ECU and the combination meter assembly for 10.6 seconds.

  • Wire harness or connector

  • Engine stop and start ECU

  • Combination meter assembly

Blinks

DTC stored

U0164

Lost Communication with HVAC Control Module

No communication between the engine stop and start ECU and the air conditioning amplifier assembly for 10.6 seconds.

  • Wire harness or connector

  • Engine stop and start ECU

  • Air conditioning amplifier assembly

Blinks

DTC stored

CAUTION / NOTICE / HINT

Tip:

If any of CAN communication system DTCs and sensor malfunction DTCs related to the CAN communication system are output simultaneously, perform troubleshooting for the CAN communication system DTCs first, then for the sensor malfunction DTCs.

PROCEDURE

  1. CLEAR DTC

    1. Connect the GTS to the DLC3.

    2. Turn the ignition switch to ON.

    3. Turn the GTS on.

    4. Enter the following menus: Powertrain / Stop and Start / Trouble Codes.

    5. Clear the DTCs.

      Powertrain > Stop and Start > Clear DTCs

    Result

    Proceed to

    NEXT
    NEXT

  2. CHECK DTC OUTPUT

    1. Turn the ignition switch off and wait for 30 seconds or more.

    2. Turn the ignition switch to ON.

    3. Start the engine.

    4. Perform a road test.

    5. Enter the following menus: Powertrain / Stop and Start / Trouble Codes.

    6. Read the DTCs.

      Powertrain > Stop and Start > Trouble Codes

      Result

      Result

      Proceed to

      DTC U0100, U0121, U0123, U0126, U0131, U0140, U0151, U0155, U0164 or U1106 is output

      A

      DTC U0100, U0121, U0123, U0126, U0131, U0140, U0151, U0155, U0164 or U1106 is not output

      B
    A

    GO TO CAN COMMUNICATION SYSTEM

    B

    USE SIMULATION METHOD TO CHECK

    Click hereClick here