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Checking voltage supply for diesel direct injection system > < Checking clutch pedal switch F36

Polo Mk3

Checking intake air temperature senderG42
Checking intake air temperature sender -G42-
  Note
In the event of a fault message, fault reader -V.A.G 1551- display shows fault code 00527 for intake manifold temperature sender-G72-.
Special tools and workshop equipment required
t  Fault reader -V.A.G 1551- or vehicle system tester -V.A.G 1552- with diagnosis cable -V.A.G 1551/3-
t  Adapter cable (68-pin) -V.A.G 1598/18A- or adapter -V.A.G 1598/22-
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 procedure
–  Connect fault reader -V.A.G 1551- or vehicle system tester -V.A.G 1552- and select engine electronics control unit with “address word 01”. Engine must be idling. (Connect fault reader -V.A.G 1551- and select engine electronics control unit → Chapter.)
   
Indicated on display:
–  Press buttons 0 and 8 for function “Read measured value block” and confirm entry with Q button.
  
Rapid data transfer                 HELP
Select function XX
Indicated on display:
–  Press buttons 0, 0 and 7 for “Display group number 7” and confirm entry with Q button.
  
Read measured value block           HELP
Input display group number XXX
Indicated on display:
–  If no realistic display appears in display zone 3 or a substitute temperature of 136.8°C is displayed, check intake air temperature sender -G42- and line connections to sender as follows:
–  Press → button.
–  Press buttons 0 and 6 for function “End data transfer” and confirm entry with Q button.
–  Switch off ignition.
  
Read measured value block 7          ->
15.4°C             15.9°C        16.7°C
–  Remove connector from intake air temperature sender -G42--arrow-.
–  Measure resistance between sender contacts.
  N23-0101
Specification see diagram.
Scale A shows resistance values for temperature range 0..50°C and scale B the values for temperature range 50..100°C.
Examples:
t  30 °C corresponds to a resistance of 1500..2000 Ω
t  80 °C corresponds to a resistance of 275..375 Ω
If the specification is not achieved:
–  Renew intake air temperature sender -G42-.
If the specification is attained:
Engine code AGD (with 68-pin control unit)
  N24-0157
–  Connect adapter cable, 68-pin -V.A.G 1598/18A- to control unit wiring harness.
  V29-0062
–  Check lines between adapter cable (68-pin) -V.A.G 1598/18A- and connector for open circuit according to current flow diagram. Contact 1 + socket 64 Contact 2 + socket 33.
Cable resistance: max. 1.5 Ω.
Engine codes AGD (with 80-pin control unit), AHG, AKU
  V96-0749
–  Connect adapter -V.A.G 1598/22- to control unit wiring harness.
  N23-0197
–  Check lines between adapter -V.A.G 1598/22- and connector for open circuit according to current flow diagram. Contact 1 + socket 13 Contact 2 + socket 25.
Cable resistance: max. 1.5 Ω.
Continuation for all engine codes
–  Also check wiring for short to one another, short to vehicle earth and short to battery positive.
Specification: ∞ Ω.
If no fault in lines is detected:
–  Renew diesel direct injection system control unit -J248- → Chapter.
  V96-0749

Checking voltage supply for diesel direct injection system > < Checking clutch pedal switch F36