Connecting Scan Tool (VAG 1551)

Ensure circuit breakers (S72 and S75), Fuse No. 19 (25-amp) and fuel pump relay check in good condition. See SYSTEM & COMPONENT TESTING - S4 article.

NOTE: Blue DLC connector is not used.
1. Open hood and remove plenum cover from under windshield. Remove cover to access Data Link Connector (DLC) in relay fuse block (Relay Station No. 1). See Fig 2 . Ensure ignition switch is in OFF position. Connect (Black) connector from adaptor cable (VAG 1551/1) to black DLC in Relay Station (note: the shape and color of the DLC when making this connection).
2. Indicated on display is 2 messages, on display line 1 "VAG ON BOARD DIAGNOSTIC". On the lower display line 2 messages will alternately between: "RAPID DATA TRANSFER" and "BLINK CODE OUTPUT".
3. If there is NO display on scan tool, verify connection for scan tool is okay. If scan tool connections are okay, check for battery voltage at DLC (Black). See CHECKING DATA LINK CONNECTOR WIRING  under ECM GROUND & VOLTAGE CHECK. Repair as necessary. Connect white adaptor cable connector to (White/Brown) DLC.
4. If display appears on scan tool, operate scan tool according to scan tool display information. See RETRIEVING DIAGNOSTIC TROUBLE CODES  , DIAGNOSTIC TROUBLE CODE IDENTIFICATION  or DIAGNOSTIC TEST MODES (DTM)  .

Fig 1: Identifying Diagnostic Scan Tool (VAG 1551)

Courtesy of AUDI OF AMERICA, INC.

Fig 2: Locating Data Link Connector (DLC)

Courtesy of AUDI OF AMERICA, INC.