SEAT Workshop Service and Repair Manuals

checking voltage supply. l  Battery voltage min. 11.5 V l  Fuse for Fuel pump control unit -J538- OK. l  Fuel pump control unit -J538- in good condition.   Note The operation of the fuel pump is checked with the actuator diagnosis.

–  Connect the central diagnosis -VAS 5051B- or central diagnosis -VAS 5052- to the diagnostics connector in the driver's side footwell. –  Switch on the ignition. –  Press buttons on display one after the other for Vehicle self-diagnosis, Engine electronics and Final control diagnosis. –  Press the right-hand side button until the fuel pump electronic actuator diagnosis is selected. The fuel pump should start running, first slowly and then gradually up to full power.   Note The fuel pump runs very quietly. –  Switch ignition OFF. If the fuel pump does not run: –  Remove the rear seat bench → Bodywork, interior fitting work; Rep. gr.72.

–  Disconnect the connector of the fuel pump control unit -J538-.

–  Check voltage supply between contacts -1- and -6- using multimeter -V.A.G 1715-. l  Specification: about the battery voltage. Voltage supply not OK: –  Locate and rectify open circuit using current flow diagram → Current flow diagrams, Electrical fault finding and Fitting locations. Power supply is okay:

–  Remove cover -1- with fuel pump control unit -J538--2- from fuel delivery unit.

–  By performing a pull check without actuating the lock, first check if the plug connector -A- has been connected correctly. If the plug connector had not been connected properly, the functional inspection of the fuel pump must be repeated. –  Remove the electrical connector. –  Check the contacts on the connector and on the fuel delivery unit for damage.   WARNING Fuel system is under pressure! Wear safety goggles and appropriate clothing to avoid injury and contact with skin. Wrap a cloth around the connection before opening the fuel system. Then release pressure by carefully loosening the connection.

–  Disconnect the fuel lines -1- and -2- from the flange.   Note t  Press in safety 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 the electrical wires between flange and fuel pump are connected. If there is cable integrity: –  Fuel pump is defective, renew fuel delivery unit → Chapter.