P0026

The content of this article / image reflects manual update #18-141-09 dated 09/11/09.



DTC P0026 INTAKE VALVE CONTROL SOLENOID CIRCUIT RANGE/PERFORMANCE (BANK 1)

1. OUTLINE OF DIAGNOSIS
Detected as NG with either Low NG or High NG.
A variable valve lift diagnosis oil pressure switch is installed for diagnosis. It is possible to determine whether the intake valve is in high mode (increase the amount of lift) or in low mode (suppressing the amount of lift) when the variable valve lift diagnosis oil pressure switch is turned ON or OFF.





Normal

Low NG
When the variable valve lift diagnosis oil pressure switch remains OFF even though the intake valve tried to enter high mode (oil switching solenoid valve duty is large), this is judged as a Low NG.

High NG
When the variable valve lift diagnosis oil pressure switch remains ON even though the intake valve tried to enter low mode (oil switching solenoid valve duty is small), this is judged as a High NG.




2. COMPONENT DESCRIPTION
The variable valve lift system optimizes the intake valve lift by switching between the low lift cam and the high lift cam according to the engine RPM. The amount of intake valve lift is varied by controlling the oil switching solenoid valve duty according to signals from the ECM.




3. ENABLE CONDITIONS




4. GENERAL DRIVING CYCLE
Perform the diagnosis continuously 6 seconds after engine start while variable valve lift is being controlled.

5. DIAGNOSTIC METHOD






Abnormality Judgment
Judge as NG when the continuous time is longer than the predetermined time when the given conditions are established.





Normality Judgment
When the continuous time is more than 3 seconds while the following conditions are established, judge as OK and clear the NG.

6. DTC CLEAR CONDITION
- When the OK idling cycle is completed 40 times in a row
- When "Clear Memory" is performed

7. MALFUNCTION INDICATOR LIGHT CLEAR CONDITIONS
- When the OK driving cycle is completed 3 times in a row
- When "Clear Memory" is performed

8. FAIL SAFE
None

9. ECM OPERATION AT DTC SETTING
Memorize the freeze frame data. (For test mode $02)