SEAT Workshop Service and Repair Manuals

Special tools, 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
• ◆ Hand multimeter V.A.G 1526 or multimeter V.A.G 1715
• ◆ Adapter set V.A.G 1594
• ◆ Current flow diagram

Check conditions

• ● Battery voltage at least 11.5 V
• ● Speedometer OK., checking:

=> Electrical system; Repair group 90

Note:

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

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.
  

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

• ‒ Input 05 for "Display group number" and confirm with Q.

Note:

If an input fault causes "Fault in the data transfer" to be displayed, pull wire off fault reader, reconnect and perform work step again.

• ‒ Carry out test drive and when doing this observe display (2nd person necessary).
• ‒ Observe displayed figure in display zone 3:
      Specification: approx. driven speed

• ‒ Press ⇒ key.
• ‒ Input 06 for "End output" and confirm with Q.
• ‒ Switch off ignition

If no speed is indicated:

Checking voltage supply

• ‒ → Pull 3 pin connector off speedometer sender (G22) -arrow-.

• ‒ → Check voltage between contacts 1+3 of detached connector.
• ‒ Switch on ignition
      Specification: At least 9 V.
• ‒ Switch off ignition
• ‒ Reconnect connector.

If no voltage was present between contacts 1+3:

• ‒ Check wiring according to current flow diagram.

If voltage was present between contacts 1+3:

• ‒ Remove dash panel insert:

=> Electrical system; Repair group 90

• ‒ → Connect test box V.A.G 1598/18 to control unit wiring loom.
• ‒ Reconnect red connector for speedometer to dash panel insert.
• ‒ Connect multimeter to measure voltage at sockets 1+65.
• ‒ Switch on ignition.
• ‒ Raise and turn left front wheel or push vehicle. The voltage figure must fluctuate between
      0...at least 4 V.

If no wiring fault is detected and voltage was present between contacts 1+3:

• ‒ Renew Motronic control unit (J220)
  => Page 24-8, item 2.

If the specification is not attained:

• ‒ Check for wiring open circuit according to current flow diagram, if necessary replace speedometer sender (G22).