DTC U011B: Lost Communication with Rocker Arm Control Module "A" [10/2017 - 12/2021]: Procedure

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

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

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

2. Turn the ignition switch to ON.
3. Measure the voltage according to the value(s) in the table below.

   Standard Voltage

   Tester Connection	Switch Condition	Specified Condition
   C51-1 (+B) - Body ground	Ignition switch ON	11 to 14 V

   Result

   Proceed to
   OK
   NG

Result: 

NG 

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

Result: 

OK 

See step  2

1. Disconnect the C51 continuously variable valve lift controller assembly connector.
2. Disconnect the C63 ECM connector.
3. Measure the resistance according to the value(s) in the table below.

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   C51-4 (CAN+) - C63-31 (CAN+)	Always	Below 1 Ω
   C51-2 (CAN-) - C63-32 (CAN-)	Always	Below 1 Ω
   C51-4 (CAN+) or C63-31 (CAN+) - Body ground	Always	10 kΩ or higher
   C51-2 (CAN-) or C63-32 (CAN-) - Body ground	Always	10 kΩ or higher

   Result

   Proceed to
   OK
   NG

Result: 

NG 

REPAIR OR REPLACE HARNESS OR CONNECTOR 

Result: 

OK 

See step  3

1. Replace the continuously variable valve lift controller assembly.

   Refer to REMOVAL [10/2017 - 08/2020] , or refer to REMOVAL [08/2020 - 12/2021]

   HINT: 

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

   Refer to INITIALIZATION [10/2017 - 12/2021]

   Result

   Proceed to
   NEXT

Result: 

NEXT 

See step  4

1. Connect the Techstream to the DLC3.
2. Turn the ignition switch to ON.
3. Turn the Techstream on.
4. Clear the DTCs.

   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.

   Powertrain > Engine and ECT > Trouble Codes 

8. Read the DTCs.

   Result

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

Result: 

A 

REPLACE ECM. Refer to  REMOVAL [10/2017 - 08/2020]  , or refer to  REMOVAL [08/2020 - 12/2021] 

Result: 

B 

END