Knock Sensor Control Limit, Testing

Knock Sensor Control Limit, Testing

If the fault message "Knock sensor - control limit reached" is recorded in the Diagnostic Trouble Code (DTC) memory the following tests must be carried out:

Test sequence
- Connect the vehicle diagnostic, testing and information system VAS 5051, Vehicle Diagnostic, Testing and Information System VAS 5051, Connecting and Selecting Functions , and select the vehicle system "01 - Engine electronics" from the menu. When doing this the engine should be idling.







Display on VAS 5051:
- Select the diagnosis function "08 - Read data block" from the menu -1-.







Display on VAS 5051:
1 - Enter display group
(figures up to 255)
- Using the keypad -2-, enter "020" to select Display group 020 and confirm entry with Q button.







Display on VAS 5051:
- Check readouts for knock control in display zones -1- to -4-.







- Press the <- button to exit from the function "08 - Read data block".

Evaluating retardation of ignition timing