Knock Control, Checking

Knock Control, Checking

Perform the following checks if a fault entry relating to "Knock control limit reached" has been stored.

Work sequence
- Connect vehicle diagnostic, testing and information system VAS 5051 and select vehicle system "01 - Engine electronics" from list. Engine must be idling. Connecting VAS 5051 Scan Tool

Indicated on VAS 5051:







- From list -1- select diagnostic function "08 - Reading measured value block".

Indicated on VAS 5051:







1 - Enter display group
- Use keypad -2- to enter "020" for "Display group number 020" and confirm by touching Q key.

Indicated on VAS 5051:







- Check display in zones -1- to -4-.

Display Group 020:

NOTE: The numerical values displayed in zones 1 to 4 represent the actual ignition timing retard by the knock control for the individual cylinders. The ignition timing is retarded in CA (degrees crank angle).

- Touch s key to switch to display group 021.

Indicated on VAS 5051:







- Check display in zones -1- to -4-.

Display Group 021:

NOTE: The numerical values displayed in zones 1 to 4 represent the actual ignition timing retard by the knock control for the individual cylinders. The ignition timing is retarded in CA (degrees crank angle).

- Terminate function "08 - Reading measured value block" by touching <- key.

Evaluation of ignition timing retard