Audi Workshop Service and Repair Manuals

Special tools and workshop equipment required

• ◆ V.A.G 1526 A
• ◆ V.A.G 1527 B
• ◆ V.A.G 1594 A
• ◆ V.A.G 1598/22
  (vehicles with engine code letters AGN)
• ◆ V.A.G 1598/31
  (vehicles with engine code letters APG)
• ◆ VAS 5051 with VAS 5051/1

Test requirement:

• ● Connect vehicle diagnosis, testing and information system VAS 5051, select "Vehicle self-diagnosis" and vehicle system "01 - Engine electronics".

Test sequence

• ‒ → Remove engine cover panel -arrows-.

→ Display on VAS 5051:

• ‒ Select diagnosis function "03 - Final control diagnosis" from the menu -1-
• ‒ Activate solenoid valve for camshaft adjuster.

• ◆ This valve is activated for about 1 minute (clicks when activated) unless the test programme is deliberately advanced to the next control element by pressing the ▸ - key.

• ‒ Press the ◂button to exit from function "03 - Final control diagnosis".
• ‒ Select diagnosis function "06 - End output".

If the valve is not actuated (does not click):

Testing internal resistance

• ‒ Switch off ignition.
• ‒ → Unplug electrical connector -arrow- from camshaft adjuster.

• ‒ → Connect multimeter to valve (resistance measurement range)
• ‒ Specification: 10 ... 18 ω

If the specification is not attained:

• ‒ Fit a new valve.

If the specification is obtained:

Testing voltage supply

Requirements for test:

• ● Fuse for solenoid valve for camshaft timing control OK

=> Current flow diagrams, Electrical fault finding and Fitting locations binder

• ● Fuel pump relay OK

=> Motronic injection and ignition system; Repair group 24

Note:

The solenoid valve for camshaft timing control receives its power supply via the fuel pump relay.

• ‒ → Unplug electrical connector -arrow- from camshaft adjuster.

• ‒ → Connect voltage tester V.A.G 1527 B as follows:

• ‒ Operate starter briefly.
• ‒ The LED should light up.

If the LED does not light up:

• ‒ Test for open circuit in wiring connection between fuel pump relay and contact 1 on connector via fuse:

=> Current flow diagrams, Electrical fault finding and Fitting locations binder

• ‒ Rectify any open circuits.

If the LED lights up:

Testing activation

• ‒ → Connect voltage tester V.A.G 1527 B to contact 1 (positive) and contact 2 of the connector.
• ‒ Start final control diagnosis and select solenoid valve for camshaft timing control:
• ‒ The LED should flash.

Models with engine code letters AGN:

If the LED lamp does not flash or if it lights up continuously:

• ‒ → Connect test box V.A.G 1598/22 to wiring harness connector. Do not connect engine control unit.

=> Motronic injection and ignition system; Repair group 24

• ‒ → Test for open circuit and short to positive or earth in the following wiring connections:

• ‒ Rectify any open/short circuit as necessary.

If the wiring is OK:

• ‒ Install a new engine control unit:

If no fault is found:

• ‒ Install a new mechanical camshaft adjuster .

Models with engine code letters APG:

If the LED lamp does not flash or if it lights up continuously:

• ‒ → Connect test box V.A.G 1598/31 to wiring harness connectors. The engine control unit itself does not need to be connected to the test box. Connect earth clamp on test box to earth -arrow-.

=> Motronic injection and ignition system; Repair group 24

• ‒ → Test for open circuit and short to positive or earth in the following wiring connections:

• ‒ Rectify any short circuits to earth or open circuits if found.

If the wiring is OK:

• ‒ Install a new engine control unit:

If no fault is found:

• ‒ Install a new mechanical camshaft adjuster => Page 15-58.