Code No. P1040: Minimum Valve Lift Not Learned Yet

FUNCTION

The engine-ECU monitors whether the initial learning for a minimum valve lift position is complete. If other diagnosis code is stored in the engine-ECU, the system cannot perform the initial learning for a minimum valve lift position.
The engine-ECU will erase the diagnosis code automatically when the system has learned the minimum valve lift position completely.

TROUBLE JUDGMENT

Check Condition

Ignition switch is "ON" position.

Judgement Criterion

The system has not completed the initial learning for a minimum valve lift position yet.

FAIL-SAFE AND BACKUP FUNCTION

None

PROBABLE CAUSE

The system has not completed the initial learning for a minimum valve lift position yet.

Malfunction of the variable valve lift mechanism.

DIAGNOSIS PROCEDURE

STEP 1. M.U.T.-III diagnosis code

Q. Is any other diagnosis code than P1040 set?

	Inspection Chart for Diagnosis Code (Refer to ).

	Go to Step 2.

STEP 2. Perform the initial learning for a minimum valve lift position, and then check whether the diagnosis code is reset.

Initialise the learned value for the MPI engine (Refer to GROUP 00 - Precautions Before Service - Initialisation Procedure for Learning Value in MPI Engine ). Then perform idling learning for the MPI engine (Refer to GROUP 00 - Precautions Before Service - Learning Procedure for Idling in MPI Engine ).
After completing the learning, erase the diagnosis code. Then check whether the diagnosis code is reset.

Q. Is diagnosis code set?

	Go to Step 3.

	Check end

STEP 3. Variable valve lift mechanism check

Variable valve lift mechanism check (Refer to GROUP 11C - On-vehicle Service - Variable valve lift mechanism check).

Q. Is the check result normal?

	Go to Step 4.

	Repair

STEP 4. Perform the initial learning for a minimum valve lift position, and then check whether the diagnosis code is reset.

Initialise the learned value for the MPI engine (Refer to GROUP 00 - Precautions Before Service - Initialisation Procedure for Learning Value in MPI Engine ). Then perform idling learning for the MPI engine (Refer to GROUP 00 - Precautions Before Service - Learning Procedure for Idling in MPI Engine ).
After completing the learning, erase the diagnosis code. Then check whether the diagnosis code is reset.

Q. Is diagnosis code set?

	Go to Step 5.

	Check end

STEP 5. M.U.T.-III diagnosis code

Reconfirmation of diagnosis code.

Q. Is diagnosis code set?

	Inspection Chart for Diagnosis Code (Refer to ).

	Intermittent malfunction (Refer to GROUP 00 - How to Use Troubleshooting/Inspection Service Points - How to Cope with Intermittent Malfunctions ).