Engine Controls - Basic Diagnostic Procedures: Overview Subaru Forester SF рестайлинг

FUEL PUMP OPERATION

Note. Electric fuel pump operation may be checked by using scan tool or by applying battery voltage to electric fuel pump. Electric fuel pump is located in fuel tank.

Scheme 1

Scheme 2

Scheme 3

Scheme 4

1. Connect diagnostic test mode connectors together and connect scan tool to data link connector (DLC). (Scheme 1)- (Scheme 4). Turn ignition on. Turn scan tool on.
2. On main menu screen of scan tool, select EACH SYSTEM CHECK and press YES key. On system selection menu, select ENGINE CONTROL SYSTEM and press YES key. After engine type information is displayed on scan tool, press YES key.
3. On engine diagnosis screen of scan tool, select SYSTEM OPERATION CHECK MODE and press YES key. On system operation check mode screen, select ACTUATOR ON/OFF OPERATION and press YES key. On actuator ON/OFF operation screen, select FUEL PUMP RELAY and press YES key. Ensure fuel pump operates for 2 seconds. If fuel pump operates, check fuel pressure. See «FUEL PRESSURE»(ref-11741-S39442570722000112700000).
4. If fuel pump does not operate, fuel pump relay may be defective. For relay operation, see «FUEL PUMP CONTROL CIRCUIT»(ref-11741-S35921169722000121200000). For testing fuel pump relay, see RELAYS in SYSTEM & COMPONENT TESTING.
5. If fuel pump relay is okay, check for defective fuses, fusible links or wiring. See WIRING DIAGRAMS article. If fuses, fusible links and wiring are okay, check for defective fuel pump. See «CHECKING FUEL PUMP OPERATION BY APPLYING BATTERY VOLTAGE TO FUEL PUMP»(ref-11741-S17617990572000121100000). If fuel pump operates properly, Engine Control Module (ECM) may be defective.

Checking Fuel Pump Operation By Applying Battery Voltage To Fuel Pump

1. Turn ignition off. Remove fuel pump access hole cover at right rear of luggage compartment (trunk on Sedans). Disconnect 6-pin electrical connector. This connector powers the fuel pump motor, fuel sending unit and fuel temperature sensor.
2. Apply battery voltage to Black/Red wire, terminal No. 1 and ground Black wire, terminal No. 4 (No. 2 on 3.0L) to activate fuel pump. DO NOT apply battery voltage to fuel pump for more than 10 seconds.
3. Listen for fuel pump operating sound. Disconnect battery voltage from fuel pump. If fuel pump operates, check fuel pressure after reinstalling components. See «FUEL PRESSURE»(ref-11741-S39442570722000112700000) . If fuel pump does not operate, replace fuel pump. See FUEL PUMP in REMOVAL, OVERHAUL & INSTALLATION article. If new fuel pump does not operate while trying to start engine, see «CHECKING FUEL PUMP OPERATION USING SCAN TOOL»(ref-11741-S19032175712000121100000) .