SEAT Workshop Service and Repair Manuals

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

• ◆ Test box V.A.G 1598/22
• ◆ Hand multimeter V.A.G 1526 or multimeter V.A.G 1715
• ◆ Adapter set V.A.G 1594
• ◆ Diode test lamp V.A.G 1527
• ◆ Current flow diagram

Check conditions

• ● The battery voltage must be at least 11.5 V.
• ● Fuse 4 must be OK.
• ● Hall sender must be OK, checking
  .
• ● Engine speed sender must be OK, checking Page 24-58.
• ● Earth connections , item 6, must be OK.

Checking voltage supply for ignition coils

• ‒ → Pull 3 pin connector -1- off ignition coil -2- for No. 1 cylinder.
• ‒ Switch ignition on.
• ‒ Connect multimeter to contacts 2 and 3 to measure voltage using auxiliary cables from V.A.G 1594.
      Specification: at least 11.0 V
• ‒ Reconnect 3 pin connector.
• ‒ Repeat check on cylinders 2, 3 and 4.

If no voltage is present:

• ‒ Connect multimeter to contact 3 and earth to measure voltage using auxiliary cables from V.A.G 1594.
      Specification: at least 11.0 V

If the specification is attained:

• ‒ Check wiring from contact 2 to engine earth using current flow diagram.

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

If voltage is still not present:

• ‒ Switch off ignition.
• ‒ Check wiring from contact 3 to relay plate according to current flow diagram.

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

Checking output stage

• ‒ Pull connector off injectors.

• ‒ → Pull 3 pin connector -1- off ignition coil -2- for No. 1 cylinder.
• ‒ Connect diode test lamp V.A.G 1527 to contacts 1 and 3 using aux. cables from V.A.G 1594
• ‒ Operate starter.
      LED must flicker
• ‒ Switch off ignition.
• ‒ Reconnect 3 pin connector.
• ‒ Repeat check on cylinders 2, 3 and 4.

If LED flickers on all cylinders:

• ‒ Check ignition coils => Page 28-15.

The LED does not flicker:

• ‒ → Pull 4 pin connector -1- off output stage -2- for ignition coils.

• ‒ → Check wire between 3 pin connector (contact 1) and respective contact on 4 pin connector of ignition coil for open circuit according to current flow diagram.
      3 pin connector    4 pin connector
      Cylinder 1 and     Contact 1
      Cylinder 2 and     Contact 4
      Cylinder 3 and    Contact 2
      Cylinder 4 and    Contact 3
      Wire resistance: Max. 1.5 ω

If no fault in wire is detected:

• ‒ Check activation of output stage => Page 28-14.

Checking activation of output stage

• ‒ Pull connector off injectors.

• ‒ → Pull 5 pin connector -1- off output stage for ignition coils -2-.
• ‒ Connect diode test lamp V.A.G 1527 using aux. cables from V.A.G 1594 to contacts 1+3.
• ‒ Operate starter and check ignition signal from engine control unit.
      LED must flicker
• ‒ Repeat check between contacts 2, 4, 5 and contact 3 (earth).

The LED does not flicker:

• ‒ Check wiring to engine control unit
  => Page 28-16

The LED does not flicker:

• ‒ Renew output stage => Page 28-2, item 2.

Checking ignition coils

• ‒ Reconnect 5 pin connector on output stage.

• ‒ → Pull 4 pin connector -1- off output stage -2- for ignition coils.
• ‒ Switch ignition on.
• ‒ Connect diode test lamp V.A.G 1527 with aux. cables from V.A.G 1594 to contact 1 of 4 pin connector and to battery negative (-)
      LED must light up.
• ‒ Repeat check between contacts 2, 3 and 4.

If LED does not flicker on one contact:

• ‒ → Check wire between 4 pin connector and respective 3 pin connector (contact 1) of ignition coil for open circuit according to current flow diagram.
      Wire resistance: Max. 1.5 ω

If no fault in wire is detected:

• ‒ Renew ignition coil.

Checking wiring

• ‒ Switch off ignition.

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

• ‒ → Check wiring between test box and 5 pin connector -1- for open circuit according to current flow diagram.
      Contact 1+socket 77
      Contact 2+socket 70
      Contact 3+socket 2
      Contact 4+socket 78
      Contact 5+socket 71
      Wire resistance: Max. 1.5 ω

If no fault in wire is detected:

• ‒ Renew engine electronics control unit => Page 24-105.