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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- or vehicle system tester -V.A.G 1552- or vehicle diagnosis and service information system -VAS 5052-
t  Diagnostic cable -V.A.G 1551/3-
t  Engine speed adjuster -V.A.G 1788/10-
  Note
t  This brief test is not available for all control units. Check if it can be performed → Rep. Gr.01.
t  Vehicle system tester -V.A.G 1552- or vehicle diagnosis and service information system -VAS 5052- can be used instead of the fault reader -V.A.G 1551-, however a print-out is not possible.
Test prerequisites
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.
Test procedure
–  Connect fault reader -V.A.G 1551- or 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 → Rep. Gr.01.
   
Indicated on display:
–  Press buttons 0 and 4 for function “Initiate basic settings” and confirm entry with Q button.
  
Rapid data transfer                 HELP
Select function XX
Indicated on display:
–  Press buttons 0, 4 and 6 for “Display group number 46” and confirm entry with Q button.
  
Initiate basic settings             HELP
Input display group number XXX
Indicated on display: (1...4 = display zones)
Vehicles ► 05.01
–  Maintain engine revolutions at 2500...4500 rpm until 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.
–  Maintain engine revolutions at 2500...4500 rpm until result of functional test is display in display zone 4 . Specification: “CatB1 OK”.
Vehicles 05.01 ►
–  Depress brake pedal and hold.
–  Depress accelerator pedal to full throttle position. Engine revolutions are raised by engine control unit to approx. 3000 rpm.
–  Allow engine to continue to run at these revolutions until temperature of catalytic converter in display zone 2 is at least 400 °C.
When diagnosis of engine control unit is initiated, display in display zone 4 jumps from “Test OFF” to “Test ON”.
–  Hold brake and accelerator pedals depressed until the result of the brief test is displayed in display zone 4: Specification “CatB1 OK”
Continuation for all vehicles
  Note
This procedure can take several minutes.
If specification “CatB1 OK” is attained:
–  Press the → button.
  
Basic setting  46                     ->
         1         2         3         4
Indicated on display:
–  Press buttons 0 and 6 for function “End data transfer” and confirm entry with Q button.
When “Cat n.OK” is display in display zone 4:
–  Take vehicle for a road test to free Lambda probe of any deposits, then repeat test.
If specification “CatB1 OK” is again not attained:
–  Renew catalytic converter.
–  Clear learnt values → Rep. Gr.24.
  
Rapid data transfer                 HELP
Select function XX

Secondary air system > < Silencer with mountings