When Replacing This Component Please Read This Procedure
INITIALIZATION PROCEDURE FOR LEARNING VALUE IN MFI ENGINEWhen the following service is performed, initialize the learning value.
^ At replacing engine assembly
^ At replacing throttle body and at cleaning
^ At replacing knock sensor
INITIALIZATION PROCEDURE
Required Special Tools:
^ MB991958: Scan Tool (M.U.T.-III Sub Assembly)
^ MB991824: V.C.I.
^ MB991827: M.U.T.-III USB Cable
^ MB991910: M.U.T.-III Main Harness A
CAUTION
^ To prevent damage to scan tool MB991958, always turn the ignition switch to the "LOCK" (OFF) position before connecting or disconnecting scan tool MB991958.
^ When the learning value for MFI engine is initialized, the initial learning value for engine timing chain elongation is also initialized. Thus, the initial learning value for timing chain elongation must be stored in scan tool MB991958 before working. If the initial learning value for timing chain elongation is not stored and the learning value for MFI engine is initialized, the visual check of the timing chain elongation must be carried out. At that time, if the timing chain elongates more than the specified value, the timing chain can possibly interfere the other parts and damage the engine before the ECM detects the timing chain elongation.
NOTE:
When the engine ASSY is replaced, the timing chain is simultaneously replaced. Thus, it is not necessary to perform Step 3 and 9.
1. After the ignition switch is in "LOCK" (OFF) position, connect scan tool MB991958 to the diagnosis connector.
2. Turn the ignition switch to the "ON" position.
3. The initial learning value for timing chain elongation must be stored in scan tool MB991958.
4. Select "MFI" from System select Screen of scan tool MB991958.
5. Select "Special Function" from MFI Screen.
6. Select "Learned value reset" from Special Function Screen.
7. Select "All learned value" from Learned value reset Screen
8. Initialize the learning value by pressing the "OK" button.
9. The stored initial learning value for timing chain elongation during Step 3 must be written into the ECM.
10. After initializing the learning value, the learning value of MFI engine idling is necessary.