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Heating of the lambda probe: verification > < Components and functions: verification

Leon Mk2

Lambda probe and lambda regulation: verification
   
Lambda probe and lambda regulation: verification
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  Electric circuits flow diagram

Test conditions
l  Coolant temperature, 85 °C minimum.
l  Exhaust system airtight between the cylinder head and the catalytic converter.
Checking process
–  Connect the equipment -V.A.G 1551- (-V.A.G 1552-). Start engine and select “Address code” 01 to select engine control unit. (Fault reader: Connecting and selecting the engine control unit → Chapter.)
   
Display indication:
–  Press the keys 0 and 8 for the function “Read measurement block values”, confirm using the key Q.
  
Rapid data transmission             HELP
Select the function XX
Display indication:
–  Press keys 0 and 0 for “Display group number” and confirm entry with Q key.
  
Read measurement block values       HELP
Input the indication group number XX
Display indication:
(1…10 = Display fields)
–  Note the value indicated in the field 1 (coolant liquid temperature).
   Specification: 22 max. (corresponding to 85 °C mín)
   If necessary, run the engine until the required temperature is reached.
–  Note the value displayed in the display field 5 (lambda probe).
   Specification: oscillating between 106…150
–  Note the value indicated in the display field 6 (recorded value in function of altitude).
  
Read measured value block              0
1    2    3   4   5   6   7   8   9   10
Workshop altitudeSpecification
0 m241…225 or 0…30
250 m235…245 or 2…24
500 m228…255 or 0…17
750 m222…255 or 0…11
1000 m215…255 or 0…4
1250 m209…254
1500 m202…247
1750 m195…240
2000 m188…233
2250 m182…227
2750 m168…213
3000 m162…207

If the specification is obtained:
–  Press the key →.
–  Press keys 0 and 6 for the “End output” function and confirm input with the Q key.
If the specification is not obtained or it is exceeded:
–  Verification of the lambda probe heating → Chapter.
–  Verify the air inlet system airtight seal (unmetered air); to do this, leave the fault reader as it was and leave the engine running → Chapter
–  Verification of the spark plugs, spark plug connections and ignition cables.
–  Verify the airtight seal of the active carbon filter solenoid valve 1. After disconnecting the ignition the valve should remain closed.
–  Check the lambda probe for soot; replace if necessary.
Check the lambda probe cable
–  Switch off ignition
   
–  Connect the tester -V.A.G 1598/18- to the control unit cable harness.
  N24-0334
–  Disconnect the 4-pin connector to the lambda probe -G39--1-.
–  Check the cable between the test box and the 4-pin connector plate for interruption following the current circuits diagram.
  N24-0343
ConnectionTest box -V.A.G 1598/18-, test box socket
315
438
Cable resistance: 1.5 Ω max.

–  Check for short circuits between the cables of the 4-pin connectors according to the electric current circuits diagram.
   Specification:∞ Ω
If the specifications are not attained:
–  Verify the connectors according to the electric current circuits diagram.
   

Heating of the lambda probe: verification > < Components and functions: verification