SFI SYSTEM, Diagnostic DTC:U011B

DTC Code DTC Name
U011B Lost Communication with Rocker Arm Control Module "A"

DESCRIPTION

The ECM and continuously variable valve lift controller assembly send signals via CAN communication.

DTC No.

Detection Item

DTC Detection Condition

Trouble Area

MIL

Memory

U011B

Lost Communication with Rocker Arm Control Module "A"

CAN communication stops (1 trip detection logic).

  • CAN communication circuit

  • Continuously variable valve lift controller assembly

  • ECM

Comes on

DTC stored

MONITOR DESCRIPTION

When between the ECM and the continuously variable valve lift controller assembly is a malfunction in the CAN communication, a DTC is stored and the MIL illuminates.

CONFIRMATION DRIVING PATTERN

  1. Connect the GTS to the DLC3.

  2. Start the engine and warm it up.

  3. Turn the GTS on.

  4. Clear the DTCs.

  5. Turn the ignition switch off and wait for at least 30 seconds.

  6. Start the engine and idle it for 20 seconds.

  7. Turn the GTS on.

  8. Clear the DTCs.

  9. Turn the ignition switch off and wait for at least 30 seconds.

  10. Start the engine and idle it for 20 seconds.

  11. Turn the ignition switch off and wait for at least 30 seconds.

  12. Turn the ignition switch to ON.

  13. Turn the GTS on.

  14. Enter the following menus: Powertrain / Engine and ECT / Trouble Codes.

  15. Read the DTCs.

WIRING DIAGRAM

A314296E09

CAUTION / NOTICE / HINT

Note:

  • When the one of the following DTCs is stored and the MIL is illuminated, DTC P1047 is stored and actuator position learning is performed every time the engine is started. Also, after the system returns to normal, the following occurs during the first driving cycle: 1) DTC P1047 is stored, 2) actuator position learning is performed and 3) the MIL illuminates during actuator position learning.

    Actuator position learning is performed when these DTCs are output.

    P1046, P1049, P104A, P1055, P2646, P2647, P2648, P2649, P264A, U011B

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

Tip:

  • When there is no power (+B) supplied to the continuously variable valve lift controller assembly, DTC U011B is stored. Also, if the SDWN circuit is open, power supply is stopped and DTC U011B is stored. After the continuously variable valve lift controller assembly power supply system and communication lines have been connected or repaired, actuator position learning is performed and DTC P1047 is stored the next time the vehicle is driven.

  • After performing repairs, perform the following procedures and check that DTCs are not output again.

  • Read freeze frame data using the GTS. The ECM records vehicle and driving condition information as freeze frame data the moment a DTC is stored. When troubleshooting, freeze frame data can help determine if the vehicle was moving or stationary, if the engine was warmed up or not, if the air fuel ratio was lean or rich, and other data from the time the malfunction occurred.

PROCEDURE

  1. CHECK TERMINAL VOLTAGE (POWER SOURCE OF CONTINUOUSLY VARIABLE VALVE LIFT CONTROLLER ASSEMBLY)

    1. A283477C03

      *a

      Front view of wire harness connected

      (to Continuously Variable Valve Lift Controller Assembly)

      Disconnect the continuously variable valve lift controller assembly connector.

    2. Turn the ignition switch to ON.

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

      Standard Voltage

      Tester Connection

      Condition

      Specified Condition

      B43-1(+B) - Body ground

      Ignition switch ON

      11 to 14 V

    Result

    Proceed to

    OK

    NG
    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR (CONTINUOUSLY VARIABLE VALVE LIFT CONTROLLER ASSEMBLY - BATTERY)

    OK

  2. CHECK HARNESS AND CONNECTOR (CONTINUOUSLY VARIABLE VALVE LIFT CONTROLLER ASSEMBLY - ECM)

    1. Disconnect the continuously variable valve lift controller assembly connector.

    2. Disconnect the ECM connector.

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

      Standard Resistance

      Tester Connection

      Condition

      Specified Condition

      B43-4 (CAN+) - B186-31 (CAN+)

      Always

      Below 1 Ω

      B43-2 (CAN-) - B186-32 (CAN-)

      Always

      Below 1 Ω

      B43-4 (CAN+) or B186-31 (CAN+) - Body ground

      Always

      10 kΩ or higher

      B43-2 (CAN-) or B186-32 (CAN-) - Body ground

      Always

      10 kΩ or higher

    Result

    Proceed to

    OK

    NG
    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  3. REPLACE CONTINUOUSLY VARIABLE VALVE LIFT CONTROLLER ASSEMBLY

    1. Replace the continuously variable valve lift controller assembly.

      Click here

      Tip:

      Perform "Inspection After Repair" after replacing the continuously variable valve lift controller assembly.

      Click here

    Result

    Proceed to

    NEXT
    NEXT

  4. PERFORM SIMULATION TEST

    1. Connect the GTS to the DLC3.

    2. Turn the ignition switch to ON.

    3. Turn the GTS on.

    4. Clear the DTC.

      Powertrain > Engine and ECT > Clear DTCs

    5. Turn the ignition switch off and wait for at least 30 seconds.

    6. Drive the vehicle in accordance with the driving pattern described in Confirmation Driving Pattern.

    7. Enter the following menus: Powertrain / Engine and ECT / Trouble Codes.

    8. Read the DTCs.

      Powertrain > Engine and ECT > Trouble Codes

      Result

      Result

      Proceed to

      DTC U011B is output

      A

      DTC is not output

      B
    A

    REPLACE ECM

    Click here

    B

    END