SEAT Workshop Service and Repair Manuals

Note:

The signal is transmitted on the data bus from the combi-instrument to the engine control unit.

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
• ◆ Current flow diagram

Check conditions

• ● Speedometer must be OK., checking speedometer:

=> Electrical system; Repair group 90

Test sequence

Note:

To check the speed signal the vehicle must be driven. To do this a second person is necessary.

• ‒ Connect fault reader V.A.G 1551 (V.A.G 1552). Start engine and select "Address word" 01 of engine control unit. When doing this the engine must be running at idling speed.
  (Connecting fault reader and selecting engine control unit .)

• ‒ Press keys 0 and 8 for the function "Read measured value block" and confirm entry with Q key.

• ‒ Press keys 0, 0 and 5 for "Display group number 5" and confirm entry with Q key.

• ‒ Carry out test drive with a 2nd person to observe display.
• ‒ Observe figure displayed in display zone 3:
      Specification: approx. driven speed
• ‒ Press the ⇒key.
• ‒ Press keys 0 and 6 for the "End output" function and confirm input with the Q key.
• ‒ Switch off ignition.

If the display does not indicate as described:

• ‒ Interrogate dash panel insert fault memory:

=> Electrical system self-diagnosis; Repair group 01

• ‒ Check wiring from combi-instrument to speed sender or automatic gearbox control unit:

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

• ‒ Check drive train data bus:

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