Volkswagen Workshop Service and Repair Manuals

Special tools, workshop equipment, testers, measuring instruments and auxiliary items required

• ◆ V.A.G 1527 B Diode test lamp

• ◆ V.A.G 1594 A Adapter set
• ◆ Current flow diagram

Check conditions

• ● Fuses must be OK.
• ● The battery voltage must be at least 11.5 V.

Functional check

• ‒ Start engine and run at idling speed.

• ‒ → Exhaust gas recirculation valve membrane rod is pulled towards vacuum hose connector (observe membrane rod through opening -arrow-). Exhaust gas is supplied.
• ‒ Increase engine speed to above 3200 rpm. The exhaust gas recirculation is switched off when 3200 rpm is exceeded (membrane moves towards exhaust gas manifold).
• ‒ Switch off ignition.

If exhaust gas recirculation does not work as described:

Check actuation of EGR valve (N18) as follows:

• ‒ → Pull 2 pin connector -2- off EGR valve (N18) -1-.
• ‒ Connect diode test lamp V.A.G 1527 using aux. cables from V.A.G 1594 to connector contacts.
• ‒ Start engine and run at idling speed.
       LED must light up
• ‒ Increase speed to over 3200 rpm.
       LED must go out

LED does not light up or go out as described:

• ‒ Check wiring according to current flow diagram. Renew automatic glow period control unit (J179) as necessary.

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

LED lights up and goes out as described:

• ‒ Check mechanical exhaust gas recirculation valve
  
• ‒ Check EGR valve (N18)
  => Page 26-13 .