Caution / Notice / Hint

NOTE:

When one of the following DTCs is output and the MIL is illuminated, actuator position learning is performed during the next trip. After the system returns to normal, actuator position learning is performed during the next trip and the MIL remains illuminated until learning is complete.

Actuator position learning is performed when these DTCs are output.
P1049, P104A, P1055, P2646, P2647, P2648, P2649, P264A, U011B

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

HINT:

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 performing repairs, perform the following procedure and check that DTCs are not output again.
Read freeze frame data using the Techstream. 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.
After using the Techstream to perform minimum valve lift learning, keep the engine idling for 30 seconds to complete learning. Otherwise, the VALVEMATIC system may not operate normally, causing poor acceleration, etc.