SEAT Workshop Service and Repair Manuals

Special tools, testers and auxiliary items

• ◆ Hand vacuum pump V.A.G 1390
• ◆ Fault reader V.A.G 1551 or vehicle system tester V.A.G 1552 with cable V.A.G 1551/3
• ◆ Test box V.A.G 1598/18
• ◆ Hand multimeter V.A.G 1526 or multimeter V.A.G 1715
• ◆ Adapter set V.A.G 1594
• ◆ Current flow diagram

Check conditions

• ● Vacuum pipes and hose connections free of leaks.
• ● Vacuum pipes not blocked/kinked.
• ● Engine oil temperature at least 50 °C

Test sequence

• ‒ Connect fault reader V.A.G 1551 (V.A.G 1552) and select engine electronics control unit (address word 01); carry out selection at idling:

=> Repair group 01; Self-diagnosis; Connecting fault reader V.A.G 1551 and selecting engine electronics control unit

• ‒ Input 08 for "Read measured value block" function and confirm with Q.

• ‒ Input 01 for "Display group number" and confirm with Q.

Only continue with the test when

• ● The coolant temperature is above 50 °C
  -Display zone 2-

• ‒ Press C key.
• ‒ Input 02 for "Display group number" and confirm with Q.

• ‒ Read off figure displayed in display zone 4.
      Specification: EGRn. active
      (exhaust gas recirculation system not active)
• ‒ Increase engine speed.
• ‒ Read off figure displayed in display zone 4.
      Specification: EGR active
      (exhaust gas recirculation system active)
• ‒ Pull vacuum hose off (mechanical) exhaust gas recirculation valve.

• ‒ → Connect hand vacuum pump V.A.G 1390 to valve with aux. hose.
• ‒ Operate pump.
      The idling characteristics must noticeably
       deteriorate.

If the idling characteristics do not deteriorate:

• ‒ Press ⇒ button.
• ‒ Input 06 for "End output" and confirm with Q.
• ‒ Switch off ignition
• ‒ Check pipes and connections for blocking, clean, if necessary replace exhaust gas recirculation valve.
• ‒ Check activation of exhaust gas recirculation valve (N18):

=> Repair group 01; Self-diagnosis; Final control diagnosis

Exhaust gas recirculation valve clicks during the final control diagnosis:

• ‒ Check wiring to exhaust gas recirculation valve temperature sensor (G98):
• ‒ Remove dash panel insert:

=> Electrical system; Repair group 90

• ‒ → Connect test box V.A.G 1598/18 to control unit wiring loom.

• ‒ → Separate 2 pin connector to exhaust gas recirculation system temperature sensor -arrow-.

• ‒ Check wiring between test box and 2 pin connector for open circuit according to current flow diagram.
      Contact 1+socket 15
      Contact 2+socket 33
      Wire resistance: Max. 1.5 ω
• ‒ → Check wiring at 2 pin connector for short to one another.
      Contact 1+socket 33
      Contact 2+socket 15
      Specification: ∞ω

If the specifications are attained:

• ‒ Replace exhaust gas recirculation temperature sensor (G98).
• ‒ Interrogate fault memory:

=> Repair group 01; Self-diagnosis; Interrogating fault memory