STEP 1. Check the variable valve lift control relay.
STEP 2. Check the continuity at valve lift ECU harness side connector.
STEP 3. Measure the power supply voltage at variable valve lift control relay harness side connector
STEP 4. Measure the power supply voltage at ECM harness side connector.
STEP 5. Measure the power supply voltage at valve lift ECU harness side connector.
(1) Disconnect the valve lift ECU connector and measure at the harness side.
(2) Short-circuit the terminal VLCR of the ECM harness connector to the ground.
(3) Measure the voltage between terminal BATM and ground.- Voltage should be battery positive voltage.
Is battery positive voltage (approximately 12 volts) present?
Go to Step 8. Go to Step 6.
STEP 6. Check of short to ground and open circuit in BATM line between variable valve lift control relay connector and valve lift ECU connector.
STEP 7. Check of harness damage in VLCR line between variable valve lift control relay connector and ECM connector.
STEP 8. Check of harness damage in BATM line between variable valve lift control relay connector and valve lift ECU connector.
STEP 9. Check of harness damage in power supply line between battery and variable valve lift control relay connector.
STEP 10. Measure the power supply voltage at ECM connector by using power plant ECU check harness special tool MB992110.
STEP 11. Check the trouble symptoms.
STEP 12. Check the trouble symptoms.
STEP 13. Test the OBD-II drive cycle.
(1) Carry out a test drive with the drive cycle pattern. Refer to Diagnostic Function - OBD-II Drive Cycle - Pattern 23 . (2) Check the diagnostic trouble code (DTC).
Is DTC P1041 stored?
Retry the troubleshooting. The inspection is complete.