Volkswagen Workshop Service and Repair Manuals

Function

The engine rpm signal output is on contact 22 of engine control unit. Amongst other things the signal is necessary for the rev. counter in dash panel insert.

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

Test conditions

• ● No faults must be stored in fault memory , interrogating and erasing fault memory.

Test sequence

• ‒ → Connect test box V.A.G 1598/31 to control unit wiring harness. The engine control unit remains disconnected.
• ‒ Check wiring from test box contact 22 to dash panel insert for open circuit referring to current flow diagram:

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