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Checking combination valve > < Checking secondary air pump motor V101

Golf Mk4

Checking activation of secondary air pump relayJ299
Checking activation of secondary air pump relay -J299-
   
–  Connect 121-pin adapter cable -V.A.G 1598/31- to control unit wiring harness. The engine control unit is also connected.
–  Bridge test box sockets 72 and 2 using adapter cables from adapter set -V.A.G 1594A-.
–  Then switch ignition on and select engine control unit with “Address word” 01.
  N24-0943
Indicated on display:
–  Operate fault reader taking into account the information on the display:
–  Press keys 0 and 3 for function “Final control diagnosis”.
  
Rapid data transfer                 HELP
Select function XX
Indicated on display:
–  Activate fuel pump relay -J17-.
–  Confirm entry with Q key.
  
Rapid data transfer                    Q
03-Final control diagnosis
Indicated on display:
  
Final control diagnosis               ->
Fuel pump relay J17
The fuel pump relay -J17- (on the relay plate, relay position 4) must click until switching to the next final control by pressing the → button (max. 50 seconds).
  Note
Bridging test box sockets 72 and 2 when activating the fuel pump relay -J17- also activates the secondary air pump relay -J299- (in protective housing for relays). It must click and the secondary air pump motor -V101- must run at intervals.
If the secondary air pump motor -V101- does not run at intervals:
  V97-6548
–  Pull 2-pin connector -arrow- off secondary air pump motor -V101- and connect diode test lamp -V.A.G 1527B- using adapter cables from adapter set -V.A.G 1594A- to disconnected connector. The LED must flash.
If LED flashes:
–  Renew secondary air pump motor -V101-:
If LED does not flash, but the secondary air pump relay -J299- clicks:
  N26-0335
–  Check wire between 2-pin connector contact 1 and body earth for open circuit.
If no wiring fault is detected:
  N24-1026
–  Pull secondary air pump relay -J299--arrow- off relay plate in protective housing for relays.
  Note
t  If tools are necessary to pull relays or control units out of the relay plate, first disconnect battery earth strap.
t  Before disconnecting battery earth strap obtain code for radios with anti-theft coding.
  N26-0347
–  Check wire for open circuit between secondary air pump motor -V101- contact 2 and contact 2 of relay plate referring to current flow diagram.
If no wiring fault is detected:
–  Check voltage supply (terminal 30) for secondary air pump relay -J299- referring to current flow diagram. → Current flow diagrams, Electrical fault finding and Fitting locations
If the voltage supply is OK:
–  Renew secondary air pump relay -J299-.
If the LED does not flash and the secondary air pump relay -J299- does not click:
  N24-1031
–  Pull secondary air pump relay -J299--arrow- off relay plate.
  Note
t  If tools are necessary to pull relays or control units out of the relay plate, first disconnect battery earth strap.
t  Before disconnecting battery earth strap obtain code for radios with anti-theft coding.
–  Connect voltage tester -V.A.G 1527B- to contacts 3 and 4 of relay plate using adapter cables from adapter set -V.A.G 1594A-: LED must flash.
LED flashes:
–  Renew secondary air pump relay -J299-.
LED does not flash:
  N26-0347
–  Connect voltage tester -V.A.G 1527B- to contact 3 of relay plate and body earth using adapter cables from adapter set -V.A.G 1594A-: LED must flash.
LED does not flash:
–  Check wire between contact 3 of relay plate and fuse 43 for open circuit referring to current flow diagram.
LED flashes:
  N24-1031
–  Disconnect 121-pin adapter cable -V.A.G 1598/31- from engine control unit. The wiring harness remains connected.
–  Remove bridge between test box sockets 72 and 2.
  N24-0943
–  Check wire for open circuit between test box socket 72 and contact 4 of relay plate referring to current flow diagram. Wire resistance: max. 1.5 Ω.
–  Check wiring additionally for short circuit to battery positive or earth..
If no wiring fault is detected:
–  Renew engine control unit → Rep. Gr.24.
  N24-1031

Checking combination valve > < Checking secondary air pump motor V101