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Home >> Audi >> 1994 >> 100 CS, 2.8 K >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Tests W/Codes >> Self-Diagnostic System >> Entering Self-Diagnostics
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Entering Self-Diagnostics

NOTE: Before entering self-diagnostics, ensure fuses are okay and fuel pump relay is okay. Press scan tester HELP button for additional trouble shooting tips or operating information. Press arrow button to step through program sequence. When prompted by scan tester, press appropriate buttons to input information, then press "Q" button to enter input.
  1. Turn ignition off. Remove cover from fuse/relay block under left side of instrument panel. See Fig 1 or Fig 2 . Connect Black connector of Scan Tester (VAG 1551) to Black connector of Data Link Connector (DLC).
  2. Idle engine (if engine will not start, operate starter for at least 5 seconds and leave ignition on). If no information is displayed on scan tester, check voltage supply to Black DLC. See CHECKING DATA LINK CONNECTORS. If scan tester alternately displays 1 - RAPID DATA TRANSFER and 2 - BLINK CODE OUTPUT, connect White connector of VAG 1551 to White connector of DLC. Blue connector is not used.
  3. Press PRINT button to turn on printer. Indicator light on PRINT button should come on. Press "1" button to select RAPID DATA TRANSFER function. Enter "01" to select ENGINE ELECTRONICS function.
  4. If any of the following messages are displayed, go to NO COMMUNICATION BETWEEN ECM & SCAN TESTER.
    • CONTROL MODULE DOES NOT ANSWER
    • COMMUNICATION MALFUNCTION
    • L- Or K-CONNECTION DOES NOT SWITCH TO GROUND/POSITIVE.
  5. If SCAN TOOL SENDS ADDRESS WORD 01 is displayed, wait for ECM identification and coding information to be displayed. Ensure information displayed matches vehicle. See ECM ENCODING.
  6. Push right arrow button. Function is now ready to be selected. To select function, input appropriate 2-digit code and press enter. For list of available functions, see SELECTABLE FUNCTIONS  table. To print a list of available functions, press HELP button. After selecting function, go to appropriate part of this article. When finished viewing displayed data, select function 06 to end output of data.
SELECTABLE FUNCTIONS

Input Number Function
02 Read DTC Memory
03 Output Diagnostic Test Mode
04 Engine Basic Setting
05 Erase DTC Memory
06 End Data Transfer
07 ECM Encoding
08 Reading Measuring Block
09 Reading Individual Measuring Values
10 (1) Adaptive Learning
(1) Applies only to ECM "B".
Fig 1: Identifying Data Link Connectors (DLC) (Except 100)
G94I45375Courtesy of AUDI OF AMERICA, INC.
Fig 2: Identifying Data Link Connectors (DLC) (100)
G94J45376Courtesy of AUDI OF AMERICA, INC.
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