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Secondary air system > < Silencer with mountings

Golf Mk4

Checking catalytic converter
   
Checking catalytic converter
Special tools and workshop equipment required
t  Fault reader -V.A.G 1551-
t  Diagnosis cable -V.A.G 1551/3C-
t  Engine speed adjuster -V.A.G 1788/10-

  Note
The vehicle system tester -V.A.G 1552- can be used instead of the fault reader -V.A.G 1551-, however a print-out is not possible.
Test procedure
l  Exhaust system between catalytic converter and cylinder head must be free of leaks
l  Coolant temperature must be at least 80 °C, ⇒ display group 04, display zone 3.
–  Connect fault reader -V.A.G 1551- (vehicle system tester -V.A.G 1552-). Start engine and select “Address word” 01 of engine control unit. Connect fault reader and select engine control unit: → engine mixture preparation; Rep. Gr.01.
–  Interrogate fault memory, if necessary, repair fault and then erase fault memory: → engine mixture preparation; Rep. Gr.01.
–  Leave fault reader -V.A.G 1551- connected.
   
Indicated on display:
–  Press keys 0 and 4 for function “Imitate basic settings” and confirm entry with Q key.
  
Rapid data transfer                 HELP
Select function XX
Indicated on display:
–  Press keys 0, 4 and 6 for “Display group number 46” and confirm entry with Q key.
  
Initiate basic settings             HELP
Input display group number XXX
Indicated on display: (1...4 = display zones)
–  Set engine speed to 2100...4500 rpm using engine speed adjuster -V.A.G 1788/10-.
–  Maintain engine speed at 2100...4500 rpm until the display in display zone 4 jumps from “Test OFF” to “Test ON”. The catalytic converter temperature in display zone 2 must be at least 400 °C.
  Note
This procedure can take several minutes.
–  Continue to maintain engine speed at 2100...4500 rpm until the result of the functional test is displayed in display zone 4. Specification: “Cat B1 OK”.
If display zone 4 displays “Cat B1n.OK”:
–  Interrogate fault memory.: → engine mixture preparation; Rep. Gr.01.
  Note
This test is intended for vehicles with On Board Diagnosis and provides information on possible damage to the catalytic converter. If “Cat B1n.OK.” is displayed: this is not an indication that the catalytic converter must be renewed. If the vehicle fails the next emissions test or the catalytic converter is physically damaged, then renew the catalytic converter.
If the emissions test fails or damage to the catalytic converter is detected:
–  Renew catalytic converter.
If the specification “Cat B1 OK” is attained:
–  Remove speed adjuster -V.A.G 1788/10- from accelerator pedal.
–  Press the → key.
  
Basic setting  46                     ->
         1         2         3         4
Indicated on display:
–  Press keys 0 and 6 for function “End data transfer” and confirm entry with Q key.
  
Rapid data transfer                 HELP
Select function XX

Secondary air system > < Silencer with mountings