DTC U011B: Lost Communication with Rocker Arm Control Module "A" [01/2019 - 03/2019]: Procedure

WARNING: This page is about a different car, the 2022 Toyota Corolla, 2021 Toyota Corolla, 2020 Toyota Corolla, and 2019 Toyota Corolla. However, it is still accessible from the selected car via links, so may be relevant.

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

Disconnect the continuously variable valve lift controller assembly connector.

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*a	Front view of wire harness connector (to Continuously Variable Valve Lift Controller Assembly)

Turn the ignition switch to ON.

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

Standard Voltage

Tester Connection	Condition	Specified Condition
C116-1 (+B) - Body ground	Ignition switch ON	11 to 14 V

Result

Proceed to
OK
NG

Result:

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

Result:

See step 2

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

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

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

Standard Resistance

Tester Connection	Condition	Specified Condition
C116-4 (CAN+) - C77-31 (CAN+)	Always	Below 1 Ω
C116-2 (CAN-) - C77-32 (CAN-)	Always	Below 1 Ω
C116-3 (SDWN) - C77-136 (SDWN)	Always	Below 1 Ω
C116-4 (CAN+) or C77-31 (CAN+) - Body ground and other terminals	Always	10 kΩ or higher
C116-2 (CAN-) or C77-32 (CAN-) - Body ground and other terminals	Always	10 kΩ or higher

Result

Proceed to
OK
NG

Result:

REPAIR OR REPLACE HARNESS OR CONNECTOR

Result:

See step 3

REPLACE CONTINUOUSLY VARIABLE VALVE LIFT CONTROLLER ASSEMBLY

Replace the continuously variable valve lift controller assembly.

Refer to REMOVAL [01/2019 - 03/2019]

HINT:

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

Refer to INITIALIZATION [01/2019 - 11/2022]

Result

Proceed to
NEXT

Result:

See step 4

CLEAR DTC

Connect the Techstream to the DLC3.
Turn the ignition switch to ON.
Turn the Techstream on.
Clear the DTCs.
Powertrain > Engine and ECT > Clear DTCs

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

Result

Proceed to
NEXT

Result:

See step 5

PERFORM SIMULATION TEST

Drive the vehicle in accordance with the driving pattern described in Confirmation Driving Pattern.
Enter the following menus: Powertrain / Engine and ECT / Trouble Codes.

Read the DTCs.

Powertrain > Engine and ECT > Trouble Codes

Result

Result	Proceed to
DTCs are not output	A
DTC U011B is output	B

Result:

END

Result:

REPLACE ECM. Refer to REMOVAL [01/2019 - 03/2019]