Read and clear fault codes from any module on the vehicle

NOTE: all the information presented is personal opinion and presented in good faith, nothing on these pages is validated or endorsed by Audi and you should be aware that you could make changes that may disable features of your car.
Always note down the original setting of anything you do and if you are not confident with what you are doing then just don't do it.

Typically if any of the warning lamps on the dash display are activated, the ECU will have recorded the fault code that has flagged the light to illuminate, alternatively any rough running may have recorded a code by number of intermittent faults recorded.

You must bare in mind that only electrical sensor errors i.e. measurable errors are recorded like component failures or tolerance discrepancies, hard problems like leaking pistons or failing components like Air Mass Meters wont necessarily show up until they have failed completely.

Examining the fault codes can give you inside information into what the dealer is going to see and may well even help you repair a fault yourself.

Some of the less serious faults or intermittent faults may just be glitches or warnings of component failure or even logged because the engine was accidentally started while a component was disconnected. For these it can be safe to clear the code and allow you to check again later to see if it returns.

Fault codes can be retrieved from modules in 2 ways, directly from the modules via the "Select Control Module" button
or you can run through the Auto-Scan to scan and report all modules.

Select your car module through the Auto Scan Chassis Type drop down box

Press Start and after about 5 minutes a summary report will be produced an example of which is below.

Alternatively individual control modules can be selected.

Below the "01" Engine Control Module is selected
Every control module has a screen similar to the example below.

Press the "02" Fault Codes button and hopefully you'll see something like the screen below.

This is an example of the Central Locking / Alarm system control module. It shows an normal alarm triggering logged fault.

If you are going to test an intermittent problem its probably best to record the code before you clear it then simply press "05" to clear the codes.