Audi Workshop Service and Repair Manuals

Checking inlet camshaft control valve 1 -N205-

Special tools and workshop equipment required

t	Hand-held multimeter -V.A.G 1526C-

t	Voltage tester -V.A.G 1527B-

t	Auxiliary measuring set -V.A.G 1594C-

t	Adapter cable, 121-pin -V.A.G 1598/31- (test box)

t	Vehicle diagnostic, testing and information system -VAS 5051B-

Procedure   Note Inlet camshaft control valve 1 -N205- and its wiring are monitored by the engine control unit. l  Vehicle diagnostic, testing and information system -VAS 5051B- connected. –  Switch on ignition and start engine.

Display on -VAS 5051B-: –  From menu -1-, select “Self diagnosis” system and press → key to activate function.

Display on -VAS 5051B-: –  From menu -1-, select vehicle system “01 - Engine electronics” system and press → key to activate function.

Display on -VAS 5051B-: –  From menu -1-, select diagnostic function “004 - Fault memory contents” and press → key to activate function.

Display on -VAS 5051B-: –  From menu -1-, select diagnostic function “004.01 - Interrogate fault memory” and press → key to activate function. If the display shows a fault relating to inlet camshaft control valve 1 -N205-: –  Terminate diagnostic function “004.01 - Interrogate fault memory” by touching ← key.

Display on -VAS 5051B-: –  From menu -1-, select diagnostic function “005 - Final control diagnosis” and press → key to activate function.

–  Press the → key repeatedly until the following display appears: Display on -VAS 5051B- (example): A -  5th control element being tested 5 -  Variable valve timing (camshaft adjustment) l  The valve will be activated intermittently for approx. 1 minute (and should click audibly). –  Terminate diagnostic function “005 - Final control diagnosis” by touching ← key. –  Select diagnostic function “022 - End output” and switch off ignition. If the valve is not activated (does not click):

Checking internal resistance –  Release quick-release fasteners and remove engine cover panel -arrows-.

–  Unplug electrical connector -arrow- at inlet camshaft control valve 1 -N205-.

–  Connect hand-held multimeter -V.A.G 1526C- to measure resistance between contacts on inlet camshaft control valve 1 -N205-. l  Specification: 10 ... 18 Ω. –  If reading does not match specification, renew inlet camshaft control valve 1 -N205-. If the specification is attained: Checking voltage supply l  Fuse for inlet camshaft control valve 1 -N205- OK → Current flow diagrams, Electrical fault finding and Fitting locations. l  Fuel pump relay -J17- OK → Current flow diagrams, Electrical fault finding and Fitting locations.   Note The inlet camshaft control valve 1 -N205- is supplied with power via the fuel pump relay -J17-.

–  Connect voltage tester -V.A.G 1527B- between contact -1- of connector for inlet camshaft control valve 1 -N205- and earth “–”. –  Briefly operate starter. l  The LED should light up. –  If LED does not light up, check for open circuit in wiring from contact -1- of connector for inlet camshaft control valve 1 -N205- via fuse to fuel pump relay -J17- → Current flow diagrams, Electrical fault finding and Fitting locations. –  If necessary repair wiring connection. If the LED lights up:

Checking activation –  Connect voltage tester -V.A.G 1527B- between contact -1 and 2- of connector for inlet camshaft control valve 1 -N205-.

–  Switch on ignition and select vehicle system “01 - Engine electronics” again. –  Repeat diagnostic function “005 - Final control diagnosis”. –  Press the → key repeatedly until the following display appears: Display on -VAS 5051B- (example): A -  5th control element being tested 5 -  Variable valve timing (camshaft adjustment) l  The LED should flash. –  Terminate diagnostic function “005 - Final control diagnosis” by touching ← key. –  Select diagnostic function “022 - End output”, switch off ignition and unplug diagnostic connector.

–  If LED does not flash or lights up continuously, connect adapter cable, 121-pin -V.A.G 1598/31- (test box) to connectors of wiring harness; do not connect engine control unit. Connect earth clip of test box to earth → Rep. Gr.24.

–  Check for open circuit and short to positive or earth in the following wiring for inlet camshaft control valve 1 -N205-.

Connector Contact	-V.A.G 1598/31- Socket
-2-	115

–  If necessary repair wiring connection. If no fault is found: –  Renew mechanical camshaft adjuster → Chapter „Removing and installing camshafts and camshaft adjuster“.