Volkswagen Workshop Service and Repair Manuals

Checking function and voltage supply l  Fuel pump relay -J17- OK l  Battery voltage at least 11.5 V. l  Fuse for fuel pump OK. Fuse assignment → Current flow diagrams, Electrical fault finding and Fitting locations   Note Function of fuel pump is checked using final control diagnosis.

–  Connect vehicle diagnosis tester as follows: –  Push diagnosis cable connector onto diagnosis connector in driver footwell. –  Switch on ignition. –  Press buttons on display one after the other for Vehicle self-diagnosis, Engine electronics and Final control diagnosis. –  Press right arrow button ► on display to initiate actuation of fuel pump. Fuel pump must be actuated in pulses. –  Switch off ignition. If fuel pump does not run: –  Remove seat bench (Golf Plus: rear right seat) → General body repairs, interior; Rep. Gr.72.

–  Remove cover from fuel delivery unit.

–  First check that the connector -arrow- is fitted securely by pulling the connector without pressing the catch. If connector was not inserted correctly, repeat functional check of fuel pump. –  Now pull off connector. –  Check the contacts on the connector and on the fuel delivery unit for damage.

–  Connect test instrument adapter/DSO (5-pin) -VAS 5565- to connector and fuel pump unit. –  Connect multimeter -V.A.G 1715- to cables -1- and -5- of test instrument adapter/DSO (5-pin) -VAS 5565-. –  Initiate final control diagnosis again. The voltage must now increase in pulses. Voltage supply not OK: –  Locate and eliminate open circuit using current flow diagram → Current flow diagrams, Electrical fault finding and Fitting locations. Voltage supply OK:   WARNING Fuel supply line is pressurised. Wear eye protection and protective clothing to avoid possible injury and skin contact. Before loosening hose connections, wrap a cloth around the connection. Then release pressure by carefully pulling hose off connection.

–  Pull fuel lines -1- and -2- off flange.   Note t  Press in securing ring to release fuel lines. t  On vehicles with auxiliary heater the connector and the fuel line of the metering pump -V54- must also be separated.

–  Open locking ring using wrench -T10202-. –  Check that electrical wires between flange and fuel pump are connected. If no open circuit can be found –  Fuel pump defective, renew fuel delivery unit → Chapter.