Volkswagen Workshop Service and Repair Manuals

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

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

Check conditions

• ● Self-diagnosis has detected a fault with the Hall sender , Interrogating and erasing fault memory.
• ● The battery voltage must be at least 11.5 V.
• ● All electrical consumers, e.g. lights and rear window heating must be switched off.
• ● If the vehicle is equipped with an air conditioning system, this must be switched off.

Test sequence

• ‒ Remove cover over camshaft housing , Fig.1 .
• ‒ → Pull 3-pin connector off Hall sender -arrow-.

• ‒ → Connect multimeter to measure voltage using aux. cables from V.A.G 1594 to contacts 1 (positive) and 3 (earth) on Hall sender connector.
• ‒ Switch on ignition.
       Specification: min. 4.5 V
• ‒ Switch off ignition.

If no voltage is present:

• ‒ → Connect test box V.A.G 1598/31 to control unit wiring harness. The engine control unit remains disconnected.

• ‒ → Check wiring for open circuit between test box and 3-pin connector referring to current flow diagram.
       Contact 1 and test box socket 96
       Contact 2 and test box socket 105
       Contact 3 and test box socket 83
       Wire resistance: max. 1.5 ω
• ‒ Additionally check wires for short to one another, to vehicle earth and to battery positive.
       Specification: ∞ω

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

• ‒ Replace Hall sender (G40)
  , item 11 .
• ‒ Interrogate fault memory, if necessary, repair any faults and then erase fault memory => Page 01-20 , interrogating and erasing fault memory.
• ‒ Erase the learnt values and adapt the engine control unit again=> Page 24-128 .

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

• ‒ Replace engine control unit
  => Page 24-121 .