Reading and Clearing Diagnostic Trouble Codes

Engine control module fault memory, interrogating and erasing
When the fault memory is erased the engine control module loses some learned values. Therefore it can lead to engine running malfunctions, depending upon the vehicle mileage.
In this case:
^ Perform a longer road test until poor driving characteristics are eliminated.
Observe the valid safety precautions when performing a road test.

Special tools, equipment, testers, measuring instruments and auxiliary items required





^ VAS5051 Vehicle Diagnosis, Testing and Information System
^ Diagnostic cable VAS5051/1 or VAS5051/3

Work sequence
^ Connect Vehicle Diagnosis, Testing and Information System VAS5051 as follows:





^ Push plug of diagnostic cable VAS5051/1 or VAS5051/3 onto Data Link Connector (arrow).
^ Start engine and run at idling speed.
Only when the engine does not start:
^ Switch on ignition.

Selecting operating mode
^ Press button on screen for"Vehicle self-diagnosis".

Selecting vehicle system
^ Press button "01 - Engine electronics" on screen.
The control module identification, the engine control module coding as well as the chassis number and immobilizer identification number are shown on the screen.

Note: A print-out can be produced if required. Press the "Print" button.

^ Press -> key.
^ Press "Print" key.

Selecting diagnostic function
^ Press button "02 - Interrogating fault memory" on screen.
^ "No fault detected" appears on screen if no faults are stored in engine control module.
^ If faults are stored in engine control module they will appear on screen listed one below another.
^ Press <-- key.
^ Press button "05 - Erase fault memory" on screen.
^ Press function 06-"End output".
^ Generate readiness code if fault memory has been erased; Refer to Adapting functions and components.

Note: Generate the readiness code if an emissions test is to be performed after erasing the fault memory or after disconnecting the engine control module from permanent positive.