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 1598/31
• ◆ VAS 5051 with VAS 5051/1

Checking internal resistance

• ‒ → Remove oil dipstick -1- from guide tube.
• ‒ Remove engine cover -arrows-.
• ‒ Reinsert dipstick in guide tube.

• ‒ Switch ignition off.
• ‒ → Detach connector for exhaust gas recirculation valve -N18 -1-.

• ‒ → Connect multimeter to injector to measure resistance.
• ‒ Specified value: 14 ... 20 ω

Note:

Resistance is in the lower tolerance range at room temperature and in the upper tolerance range when the engine is warm.

If specified value is not attained:

• ‒ Replace the exhaust gas recirculation valve -N18.

Checking power supply

• ‒ → Connect multimeter between contact 1 and earth to measure voltage.
• ‒ Switch the ignition on.
• ‒ Specified value: approx. battery voltage

If specified value is not attained:

• ‒ Check wiring for open circuit and service if necessary.

Checking actuation

• ● Vehicle diagnostic, testing and information system VAS 5051 connected, vehicle self-diagnosis and vehicle system "01 - Engine electronics" selected.

• ‒ → Connect voltage tester V.A.G 1527 B between contacts 1 and 2.

→ Display on VAS 5051:

• ‒ Under -1- select the diagnostic function "03 - Final control diagnosis".

→ Display on VAS 5051:

•     A -    1st control element in test
•     1 -    EGR valve -N18
• ‒ The LED must flash slowly.

Note:

Voltage testers with a low current consumption continue to glow faintly between actuation from the engine control unit (rather than extinguishing completely) and become much brighter when actuated.

• ‒ End function "03 - Final control diagnosis" by pressing the ◂ key.
• ‒ Press "06 - End output".

If the LED lamp does not react as described:

• ‒ → Connect the V.A.G 1598/31 test box to wiring harness connectors; the engine control unit should not be connected. Attach the earth clip of test box to earth -arrow-.

=> TDIInjection and Glow Plug System(4-cyl Pump Jet); Repair group 23

• ‒ → Test for open circuit in the following wiring connections.

• ‒ Rectify any open/short circuit as necessary.