seat Workshop Repair Guides

SEAT Workshop Service and Repair Manuals

ABOUT US
Injectors: checking > < Additional checking if the fault was recorded in the memory as ?sporadic/SP?:

Leon Mk2

Intake air temperature sender: checking
   
Intake air temperature sender: checking
Special tools and workshop equipment required
t  Hand multimeter -V.A.G 1526 A- or multimeter -V.A.G 1715-
t  Fault reader -V.A.G 1551- or vehicle system tester -V.A.G 1552- with cable -V.A.G 1551/3B-
t  Auxiliary measuring set -V.A.G 1594 C-
t  Test box -V.A.G 1598/18-
t  Current flow diagram
t  Chilling spray (commercially available)

Checking process
  Note!
If there is a fault in the sender or the wiring, the control unit will work with a replacement temperature of 20 °C .
–  Connect fault reader -V.A.G 1551- (-V.A.G 1552-). Then switch ignition on and enter “address code” 01 to select engine control unit. (Fault reader: Connecting and selecting the engine control unit → Chapter.)
   
Indicated on the display:
–  Press keys 0 and 8 for the function “Read measured value block” and confirm entry with the Q key.
  
Rapid data transfer                 HELP
Select function XX
Indicated on the display:
–  Press keys 0, 0 and 2 for “Display group number 2” and confirm entry with the Q key.
  
Read measured value block           HELP
Input display group number XXX
Indicated on the display: (1…4 = display zones)
–  Read intake air temperature value in display zone 4.
  
Read measured value block 2           ->
         1         2         3         4
IndicatedCauseContinuation of check
approx. -33 °COpen circuit or short to positive →  
approx. 118 °CShort to earth →  
Approx. ambient temperature → Note— →  

1)  If a temperature is displayed which is below the ambient air temperature of the sender, check first the sender wiring for transfer resistances. Note that sender may be heated by radiated heat when engine is not running.
If the display indicates approx. -33 °C, continue checking as follows:
   
–  Pull connector -1- off the intake air temperature sender -G42- with intake manifold pressure sender -G71--2-.
–  Bridge connector contacts 1+2 with auxiliary cables from -V.A.G 1594 C- and observe display.
Display value approx. 118 °C
–  Press the → key.
–  Press keys 0 and 6 for the “End output” function and confirm input with the Q key.
–  Switch ignition off.
–  Renew the intake manifold temperature sender -G42- with intake manifold pressure sender -2- → Item.
Display value approx. -33° C:
–  Press the → key.
–  Press keys 0 and 6 for the “End output” function and confirm input with the Q key.
–  Switch ignition off.
  N24-0307
–  Connect test box -V.A.G 1598/18- to control unit wiring harness.
–  Check the wiring between test box and 4-pin connector for open circuit using current flow diagram.
  N24-0334
ContactTest box -V.A.G 1598/18-, socket
243
Wire resistance: 1,5 Ω max.

–  Check wiring additionally for short circuit to battery positive.
   Specification: ∞ Ω
–  Check the wiring between test box and 4-pin connector for open circuit using current flow diagram.
   
ContactTest box -V.A.G 1598/18-, socket
117
Wire resistance: 1,5 Ω max.

If no wiring fault is detected:
–  Replace the engine control unit → Item
If the display indicates approx. 118 °C, continue checking as follows:
   
–  Pull connector -1- off the intake air temperature sender -G42- with intake manifold pressure sender -G71--2-.
Display value approx. -33° C:
–  Press the → key.
–  Press keys 0 and 6 for the “End output” function and confirm input with the Q key.
–  Switch ignition off.
–  Renew the intake manifold temperature sender -G42- with intake manifold pressure sender -2- → Item.
Display value approx. 118° C:
–  Press the → key.
–  Press keys 0 and 6 for the “End output” function and confirm input with the Q key.
–  Switch ignition off.
–  Remove the connector of the engine control unit.
–  Check the wiring to the control unit connector at 4-pin connector, contact 2, for short circuits to wire contact 1 and vehicle earth.
   Specification: ∞ Ω
If no wiring fault is detected:
–  Replace the engine control unit → Item
Continuation of check when display = ambient temperature:
  N24-0305
–  Remove intake air temperature sender together with intake manifold pressure sender (connector remains connected).
–  Note intake air temperature value in display zone 4.
–  Spray sender with commercial chilling agent while observing the temperature value. The temperature value should fall.
–  Press the → key.
–  Press keys 0 and 6 for the “End output” function and confirm input with the Q key.
  N24-0320

Injectors: checking > < Additional checking if the fault was recorded in the memory as ?sporadic/SP?: