Volkswagen Workshop Service and Repair Manuals

Special tools, testers, measuring instruments and auxiliary items required

• ◆ Fault reader V.A.G 1551 (or vehicle system tester V.A.G 1552) with cable V.A.G 1551/3

Work sequence

• ‒ Connect fault reader V.A.G 1551 (V.A.G 1552) and select engine electronics control unit with the "Address word" 01. When doing this the engine must be running at idling speed.
  (Connecting fault reader and selecting engine electronics control unit .)

Only when engine does not start:

• ‒ Operate the starter for at least 5 seconds. Then do not switch the ignition off.

• ‒ Switch on fault reader printer with the print key. The warning lamp in key must light up.

• ‒ Operate fault reader taking into account the information on the display:
• ‒ Press keys 0 and 2 for function "Interrogate fault memory" and confirm entry with Q key.

If no fault is stored:

• ‒ Press ⇒key.

If one or more faults are stored:

The stored faults will be displayed and printed out one after the other.

• ‒ Press keys 0 and 5 for the function "Erase fault memory" and confirm entry with Q key.

Note:

If the ignition is switched off between "Interrogate fault memory" and "Erase fault memory" the fault memory will not be erased.

• ‒ Press ⇒key.

• ‒ Press keys 0 and 6 for the function "End output" and confirm entry with the Q key.
• ‒ Eliminate the faults printed out using the appropriate fault table.
  => Page 01-14 .

During test and assembly work faults can be recognised from other control units like e.g. plug disconnected. Therefore on completion the fault memories of all control units must be interrogated and erased. To do this:

• ‒ Press key 0 twice for address word "Automatic test sequence" and confirm entry with Q key. The V.A.G 1551 transmits all known address words one after the other.

When a control unit answers with its identification the number of stored faults appears on the display or "No fault recognised".

Any system faults that are stored will be displayed one after the other and printed out. The V.A.G 1551 will then transmit the next address word.

• ‒ Erase all fault memories and then carry out a road test.

• During the road test the following operating conditions must be fulfilled:
• ‒ The coolant temperature must exceed 80 °C .
• ‒ When the temperature is reached, the operating conditions
       Idling
       Part throttle
       Full throttle
       Overrun
  must be attained several times.
• ‒ At full throttle the speed must exceed 3500 rpm.

• ‒ Again interrogate the fault memories of all control units using the "automatic test sequence".

If no fault is stored:

• ‒ Press the ⇒key.

• ‒ Press keys 0 and 6 for the function "End output" and confirm entry with the Q key.

Note:

If the self-diagnosis has not detected a fault, use the appropriate fault table in "Fault finding engine" binder for further fault finding.