Audi Workshop Service and Repair Manuals

Special tools and workshop equipment required

• ◆ Speed adjuster V.A.G 1788/10

Preconditions:

• ● Vehicle stationary.
• ● Vehicles with automatic gearbox: Selector lever in position P or N
• ● Electrical consumers switched off (radiator fan must not run during the test)
• ● Air conditioning switched off.
• ● Coolant temperature at least 80 °C=> display group 004, display zone 3. Important: Run engine warm possibly through test drive.

Important note:

If the test result "OK" is displayed immediately within a test step after selecting the display group the test has already run and the next operating step can be carried out.

Operating step 1: Interrogating fault memory

Test conditions:

• ● Engine stopped, ignition switched on

• ‒ Connect vehicle diagnostic, testing and information system VAS 5051 or fault reader V.A.G 1551 and select engine electronics control unit with "Address word" 01

• ‒ Enter "02" for the function "Interrogate fault memory" and confirm entry with Q key.

If no fault is stored:

• ‒ Rectify any faults and erase the fault memory. Perform a road test and interrogate the fault memory again as a check.

If no fault is stored:

• ‒ Press the ⇒key.

Operating step 2: Erasing fault memory

Test conditions:

• ● Engine stopped, ignition switched on

• ‒ Enter "05" for the function "Erase fault memory" and confirm entry with Q key.

Note:

When erasing the fault memory the readiness code is reset and therefore must be produced again.

• ‒ Press the ⇒key.

Adaption of throttle valve control unit to the engine control unit

Test conditions:

• ● Engine stopped, ignition switched on

• ‒ Enter "04" to select "Start basic setting" and confirm with Q key.

• ‒ Enter "060" for "display group number 060" and confirm entry with Q key.

• ‒ Check specified values in display zones 3 and 4:

Note on display zone 3:

During adaption different figures are shown in display zone 3 which illustrate the relevant adaption condition. The deciding factor is not how the learning stage counter (display zone 3) behaves during the adaption process, but that specified value in display zone 4 of specified value "ADP OK" has been attained after adaption.

If specified value "ADP OK" is attained:

• ‒ Press C key.

Operating step 4: Adapt kickdown function 1)

    1)    Only on vehicles with automatic gearbox.

Test conditions:

• ● Engine stopped, ignition switched on

• ‒ Enter "063" for "display group number 063" and confirm entry with Q key.

Note:

You will now be instructed to: "Confirm kickdown".

• ‒ Fully depress accelerator pedal beyond kickdown point and keep it pressed.

Note:

During adaption the kick-down point "Kick-down ADP is running" is displayed on V.A.G 1551. After successful adaption of the kick-down point the V.A.G 1551 shows "Kick-down ADP OK".

• ‒ Check specified value in display zone 4:

Note on display zone 4:

If "ERROR" can be displayed, if e.g. accelerator pedal is not pressed when instructed by tester, or if accelerator pedal was released while adaption was already running but process was not yet complete.

In both cases it is necessary to exit the "Basic setting" mode and restart the adaption process afresh.

If specified value "ADP OK" is attained:

• ‒ Press C key.

Operating step 5: Check operating status of lambda control

• ‒ Start the engine (in vehicle with manual gearbox: press clutch pedal).

Note:

If necessary, reselect the engine control unit with "address word" 01 after starting the engine and initiate function "basic setting" with "04".

• ‒ Adjust speedometer V.A.G 1788/10 on accelerator pedal and increase speed to 2600 rpm.

Test conditions:

• ● Engine runs at 2600 rpm.

• ‒ Enter "030" for "display group number 030" and confirm entry with Q key.

• ‒ Check lambda probe status in display zones 1 to 2.

Note:

Several minutes may pass until reaching a diagnostic result.

Notes:

• ◆ The first digit of the 3-digit display (heating) fluctuates between 0 and 1 at certain operating points.
• ◆ The lambda control of lambda probe downstream of catalytic converter (bank 1, probe 2) is not active without engine load, i.e. the display of the 3-digit display is 0.

• ‒ Only continue with the test if the displays have reached "111" in display zone 1 and "110" in display zone 2 at least once.

Operating step 6: Diagnosis of ageing of lambda probe upstream of catalytic converter

Test conditions:

• ● Engine continues running at 2600 rpm.

• ‒ Enter "034" for "display group number 034" and confirm entry with Q key.

• ‒ Check specified value in display zone 4:

Note:

Several minutes may pass until reaching a diagnostic result.

If specified value "B1-S1 OK" is attained:

• ‒ Press C key.

Operating step 7: Diagnosis of lambda probe condition downstream of catalytic converter

Test conditions:

• ● Engine continues running at 2600 rpm.

• ‒ Enter "036" for "display group number 036" and confirm entry with Q key.

• ‒ Check specified value in display zone 2:

If specified value "B1-P2 OK" is attained:

• ‒ Press C key.

Operating step 8: Diagnosis of lambda control system

Test conditions:

• ● Engine continues running at 2600 rpm.

• ‒ Enter "037" for "display group number 037" and confirm entry with Q key.

• ‒ Check specified value in display zone 4:

If specified value "Syst. OK" is attained:

• ‒ Press C key.

Operating step 9: Diagnosis of ageing of lambda probes downstream of catalytic converter

Test conditions:

• ● Engine continues running at 2600 rpm.

• ‒ Enter "043" for "display group number 043" and confirm entry with Q key.

• ‒ Check specified value in display zone 4:

If specified value "B1-P2 OK" is attained:

• ‒ Press C key.

Operating step 10: Diagnosis catalytic converter

Test conditions:

• ● Engine continues running at 2600 rpm.

• ‒ Enter "046" for "display group number 046" and confirm entry with Q key.

• ‒ Check specified values in display zones 2 and 4:

Note:

The time of the test of the catalytic converter diagnosis is approx. 60 seconds.

If the specified value "Cat B1 OK" is attained:

• ‒ Press C key.

Operating step 11: Diagnosis of fuel tank breather valve

• ‒ Remove speedometer V.A.G 1788/10 and let engine run at idling speed.

Test conditions:

• ● Engine running at idling speed

• ‒ Enter "070" for "display group number 070" and confirm entry with Q key.

• ‒ Check specified value in display zone 4:

Note:

If the test is not initiated or if the display jumps from "Test ON" to Test "OFF" accelerate briefly, test is repeated.

If specified value "TEV OK" is attained:

• ‒ Press C key.

Operating step 12: Diagnosis of secondary air system

Test conditions:

• ● Engine running at idling speed

Note:

If the diagnosis of the secondary air system the secondary air pump runs several seconds.

• ‒ Enter "077" for "display group number 077" and confirm entry with Q key.

• ‒ Abruptly floor the accelerator pedal and release again (brief burst of throttle). 2500 rpm.
• ‒ Check specified value in display zone 4:

Note:

The time of the test of the secondary air system is approx. 60 seconds.

If specified value "Syst. OK" is attained:

• ‒ Press the ⇒key.

Operating step 13: Read out readiness code

• ‒ Read out readiness code => Page 01-65.