Connecting the tester (VW Polo 3)

All functions can be performed using the VAG 1551/1552 fault code reader. They can also be performed using the new VAS 5051 tester in the engine self-diagnosis operating mode.

In this case, the following requirements must be met:

• fuses 1, 3, 11, 15, 23, 30, 31, 32, 34, 36, 37, 39 and 40 must be in working order;
• battery voltage must be at least 11.5V;
• the ground connection between the engine and the body must be in good condition.

1. Move cover 1 in the direction of the arrow (Fig. 4.29). Connect the wiring connector from the diagnostic cable of the VAS 5051/1 and VAS 5051/3 testers to the diagnostic connector.



2. After connecting the fault code reader, depending on the selected function, turn on the ignition or start the engine.

3. Press the "Vehicle Self-Diagnostics" button on the display.

4. Press "01" "Engine Electronics" on the display. The display should show the identification number and engine code.

5. If the engine code differs from the vehicle version, check the control unit coding and, if necessary, re-code.

Connecting the VAG 1551 fault code reader

6. Connect the VAG 1551 fault code reader using the VAG 1551/3 cable.



7. After connecting the fault code reader, depending on the selected function, turn on the ignition or start the engine.

8. The display should show the following information:


9. Press "1" to select the "Data Transfer" function. Press "01" to select "Engine Electronics" and confirm with the "Q" button. The display should show the following information:


6K090634C - Engine control unit number.
MARELLI 4LV - Version and designation of the injection system.
2615 - Program version number.
Code 00011 - Control unit code.
WSC XXXXX - Code from VAG 1551.

10. If the engine code differs from the vehicle version, check the control unit coding and, if necessary, re-code.

11. Press "→". The display should show the following information:



12. For further measurements, see the repair procedure.