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Checking engine speed sender G28 > < Checking components and functions

Polo Mk3

Checking voltage supply for diesel direct injection system
Checking voltage supply for diesel direct injection system
Special tools and workshop equipment required
t  Adapter cable, 121-pin -V.A.G 1598/31-
t  Hand multimeter -V.A.G 1526C- or multimeter -V.A.G 1715-
t  Auxiliary measuring set -V.A.G 1594C-
t  Current flow diagram
Test prerequisites:
l  Battery voltage OK. (at least 11.5 V)
Test procedure
–  Switch off ignition.
   
–  Connect adapter cable, 121-pin -V.A.G 1598/31- to control unit wiring harness.
–  Measure voltage between the following sockets:
1/2 and 4/5
37 and 4/5
Specification: approx. 0 V
–  Switch on ignition.
–  Measure voltage again between the sockets:
1/2 and 4/5
37 and 4/5
Specification: approx. battery voltage
If the specifications are not attained:
–  Check terminal 30 voltage supply relay -J317-.
–  Check cable connections for open circuit, short circuit and transfer resistance at contacts according to current flow diagram.
If no fault is found in wiring and relay:
–  Renew diesel direct injection system control unit -J248- → Chapter.
  N23-0378

Checking engine speed sender G28 > < Checking components and functions