seat Workshop Repair Guides

SEAT Workshop Service and Repair Manuals

Checking injectors > < Checking intake air temperature sender
Motronic injection and ignition system (6-cylinder engine)
Checking components
Checking engine speed sender

The engine speed sender (G28) is a speed and reference mark sender. The engine will not start if there is no speed signal. If the speed signal fails when the engine is running, it will cause the engine to stall immediately.

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

  • ◆ 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 1598/31
  • ◆ Hand multimeter V.A.G 1526 or multimeter V.A.G 1715
  • ◆ Adapter set V.A.G 1594
 
N24-1284
  • ◆ Current flow diagram

Test sequence

  • ‒ → Separate grey 3-pin connector -arrow- to engine speed sender.
 
M24-0052
  • ‒ → Measure sender resistance between contacts 2 + 3 of connector to sender.
        Specification: 480...1000 ω
  • ‒ Check the sender for short between contacts 1 + 2 as well as 1 + 3.
        Specification: ∞ω

If the specifications are not obtained:

  • ‒ Renew engine speed sender (G28).
  • ‒ Interrogate fault memory, if necessary, repair any faults and then erase fault memory , interrogating and erasing fault memory.
 
N24-1200
  • ‒ Read-out the readiness code=> Page 01-64.

If no sender fault is detected:

  • ‒ Remove battery.
  • ‒ → Connect test box V.A.G 1598/31 to control unit wiring harness. The engine control unit remains disconnected.
 
A24-0096
  • ‒ → Check wiring for open circuit between test box and 3-pin connector using current flow diagram.
        Contact 1+socket 108
        Contact 2+socket 90
        Contact 3+socket 82
        Wire resistance: Max. 1.5 ω
  • ‒ Additionally check wires for short to one another.

If no wiring fault is detected:

  • ‒ Remove sender and check sender wheel for secure fit, damage and run-out.

Note:

There is a larger gap on the sender wheel. This gap is the reference mark and does not mean that the sender wheel is damaged.

If no fault is detected on sender wheel:

  • ‒ Replace engine control unit
    => Page 24-150.

Checking injectors > < Checking intake air temperature sender