SEAT Workshop Service and Repair Manuals

Special tools, testers and auxiliary items

• ◆ 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

Test conditions

• ● Engine cold

Test sequence

• ‒ Connect fault reader V.A.G 1551 (V.A.G 1552) and with the "Address word" 01 select the engine electronics control unit. When doing this the engine should be idling.
  (Connecting fault reader and selecting engine electronics control unit .)

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

• ‒ Press keys 0 and 1 for "Display group number 01" and confirm entry with Q key.

Functional check of sender

• ‒ Observe coolant temperature figure in display zone 2. The temperature figure must
      increase uniformly and without interruption.

• If a temperature figure is displayed which deviates greatly from the senders ambient temperature, check sender wiring for transfer resistances.

Notes:

• ◆ Depending upon the temperature level, the display on fault reader will jump by 2...5 °C

• ◆ If irregular engine running occurs in certain temperature ranges and the temperature figure does not increase without interruption, the temperature signal is temporarily interrupted and the sender must be renewed.

• ‒ Press the ⇒key.
• ‒ Press keys 0 and 6 for the "End data transfer" function and confirm input with the Q key.

If the figure does not increase uniformly:

• ‒ Renew coolant temperature sender (G62).

If a G62 fault is indicated in fault memory even though the figure increases uniformly:

• ‒ Switch off ignition.
• ‒ → Pull 4 pin connector -1- off coolant temperature sender (G62) -2-.

• ‒ → Check coolant temperature sender resistance between contacts 1+3.
      Specification: => Page 24-18, Fig. 1

If the specification is not obtained:

• ‒ Renew coolant temperature sender (G62).

If the specification is attained:

• ‒ Remove dash panel insert.

=> Electrical system; Repair group 90

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

• ‒ → Check wiring between test box and 4 pin connector for open circuit according to current flow diagram.
      Contact 1+socket 35
      Contact 3+socket 12
      Wire resistance: Max. 1.5 ω
• ‒ Check wire between control unit connector and 4 pin connector contact 3 for short to wire contact 1 as well as to vehicle earth, according to current flow diagram.
      Specification: ∞ω
• ‒ Check wiring additionally for short circuit to battery positive.
      Specification: ∞ω

If no fault in wire is detected and the coolant temperature sender is OK:

• ‒ Renew Simos control unit (J361)
  , item 14.