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Volkswagen Workshop Service and Repair Manuals

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Checking speed signal > < Checking intake manifold temperature sender

Golf Mk3

Motronic injection and ignition system (4-Cyl. engine)
Motronic injection and ignition system
Checking coolant temperature sender

Special tools, testers and auxiliary items

  • ◆ Fault reader V.A.G 1551 with cable V.A.G 1551/3

Test conditions

  • ● Engine cold

Test sequence

  • ‒ Connect fault reader V.A.G 1551 and select engine electronics control unit (address word 01); selection is carried out with engine idling .
 
→ Indicated on display:
Rapid data transmission     HELP
Select function XX
  • ‒ Input 08 for "Read measuring value block" function and confirm with Q.
 
→ Indicated on display:
Reading measuring value block     HELP
Input display group number XX
  • ‒ Input 01 for display group 01 and confirm with Q.
 
→ Indicated on display:
(1...4 = Display zones)
Read measuring value block 1     ⇒
     1     2     3     4

Note:

If something different is indicated on the display:

=> Fault reader operating instructions

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

Notes:

  • ◆ If the display on fault reader jumps by 2...5 °C, this is caused by the control unit and not by a defective sender.
  • ◆ With ignition switched on -49 °C is indicated.
  • ◆ Open circuit is indicated by - 25.9 °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 ⇒ button.
  • ‒ Input 06 for "End output" and confirm with Q.

If the temperature figure does not change:

  • ‒ Carry out electrical check, test step 18
    => Page 24-9 , item 17 .

Checking speed signal > < Checking intake manifold temperature sender