Section 29 (Engine Controls - System/Component Tests): Introduction
WARNING: This page is about a different car, the 1993 Volkswagen Fox. However, it is still accessible from the selected car via links, so may be relevant.
Since many computer-controlled and monitored components set a trouble code if they malfunction, also perform procedures in the TESTS W/CODES article. In most instances, Scan Tester (VAG 1551) must be used to test systems and/or components. See ENTERING SELF-DIAGNOSTICS in the appropriate TESTS W/CODES article for additional scan tester operating instructions.