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 the fuel tank.
Checking Fuel Pump Operation Using Scan Tool (Camry, Camry Solara, Celica, RAV4, Tacoma & 4Runner)
- Connect scan tool to data link connector No. 3. (Scheme 1)- (Scheme 7). Turn ignition on. DO NOT start engine.
- Turn scan tool on. Select ACTIVE TEST MODE on scan tool. Using scan tool manufacturer's instructions, activate fuel pump. Listen for fuel pump operating sound and feel for fuel pressure in fuel inlet line at fuel filter. Turn ignition off. Remove scan tool. If fuel pump operates, check fuel pressure. See «FUEL PRESSURE»(ref-91199-S19863421532001030500000).
- If fuel pump does not operate, EFI main relay or circuit opening relay may be defective. For relay application and explanation of relay operation, see «FUEL PUMP CONTROL CIRCUIT»(ref-91199-S37932389432001030500000). For testing of EFI main relay or circuit opening relay, see RELAYS in SYSTEM & COMPONENT TESTING - 4-CYLINDER article.
- If relays are okay, check for defective fuses, fusible links or wiring. See appropriate wiring diagram in 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-91199-S25358720592001030500000). If fuel pump operates properly, Engine Control Module (ECM) may be defective.
Checking Fuel Pump Operation Using Scan Tool (Corolla)
- Connect scan tool to data link connector No. 3. (Scheme 4) Turn ignition on. DO NOT start engine.
- Turn scan tool on. Select ACTIVE TEST MODE on scan tool. Using scan tool manufacturer's instructions, activate fuel pump. Listen for fuel pump operating sound and feel for fuel pressure in fuel inlet pipe at end of fuel rail. Turn ignition off. Remove scan tool. If fuel pump operates, check fuel pressure. See «FUEL PRESSURE»(ref-91199-S19863421532001030500000).
- If fuel pump does not operate, EFI main relay or circuit opening relay may be defective. For relay application and explanation of relay operation, see «FUEL PUMP CONTROL CIRCUIT»(ref-91199-S37932389432001030500000). For testing of EFI main relay or circuit opening relay, see RELAYS in SYSTEM & COMPONENT TESTING - 4-CYLINDER article.
- If relays are okay, check for defective fuses, fusible links or wiring. See appropriate wiring diagram in 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-91199-S25358720592001030500000). If fuel pump operates properly, Engine Control Module (ECM) may be defective.
Scheme 1
Scheme 2
Scheme 3
Scheme 4
Scheme 5
Scheme 6
Scheme 7
Checking Fuel Pump Operation By Applying Battery Voltage To Fuel Pump
- On Camry, Camry Solara, Celica and Corolla, remove rear seat and cover plate on floor panel for access to electrical connector for fuel pump.
- On RAV4, remove driver's side rear seat and cover plate on floor panel for access to electrical connector for fuel pump.
- On Tacoma and 4Runner, it may be necessary to lower fuel tank for access to electrical connector for fuel pump.
- On all models, disconnect electrical connector for fuel pump. This is electrical connector for fuel pump and fuel gauge sending unit.
- Connect battery voltage to specified terminals on fuel pump to activate fuel pump. (Scheme 8)- (Scheme 13). DO NOT apply battery voltage to fuel pump for more than 10 seconds.
- 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-91199-S19863421532001030500000).
- If fuel pump fails to operate, replace fuel pump and/or lead wire to fuel pump (if equipped). See FUEL SYSTEM in REMOVAL, OVERHAUL & INSTALLATION - 4-CYLINDER article. If fuel pump will not operate while trying to start engine, see appropriate CHECKING FUEL PUMP OPERATION USING SCAN TOOL under «FUEL PUMP OPERATION»(ref-91199-S39547796742001030500000) for additional testing information.
