Volkswagen Workshop Service and Repair Manuals

Only engine code AUC

Special tools, workshop equipment, test and measuring appliances and auxiliary items required

• ◆ V.A.G 1526 Hand multimeter
• ◆ V.A.G 1594 A Adapter set
• ◆ V.A.G 1598/22 Test box
• ◆ Current flow diagram

Test conditions

• ● → Fuses 30, 31 and 36 must be OK.

Test sequence

• ‒ → Pull off 6-pin connector -1- (grey) from EGR valve.

• ‒ → Connect multimeter to contacts 2 and 4 of 6-pin connector for voltage measurement.
• ‒ Switch on ignition.
       Specification: min. 4.5 V

• ‒ Switch off ignition.

• ‒ → Connect test box V.A.G 1598/22 to control unit wiring harness.

• ‒ → Check wiring for open circuit between test box and 6-pin connector using current flow diagram.
       Contact 2 and test box socket 62
       Contact 4 and test box socket 54
       Contact 6 and test box socket 69
       Wire resistance: max. 1.5 ω
• ‒ Additionally check wiring for short to one another, and for short to positive or earth.
• ‒ Depending on conditions, renew following components:

Voltage supply and wiring OK:

• ‒ Renew EGR valve (N18) with potentiometer (G212).
• ‒ Erase learnt values and re-adapt engine control unit

=> Repair group 24; Engine control unit; Adapting engine control unit to throttle valve control part

If no wiring fault is detected and voltage supply is not OK:

• ‒ Renew engine control unit.

=> Repair group 24; Engine control unit; Renewing engine control unit