[ Model - ECLIPSE CROSS / Year - 2018 ]
2018 / ECLIPSE CROSS / EC - Workshop Manual
13 -FUEL > 13A-DIRECT INJECTION AND MULTIPOINT FUEL INJECTION (DI AND MPI) > TROUBLESHOOTING > SYMPTOM PROCEDURES > FUEL PUMP SYSTEM
Inspection Procedure 25: Fuel Pump System
 
 
 
 
OPERATION
  • The fuel pump drive power is supplied from engine control relay to fuel pump relay (ETACS-ECU connector terminal F/PB) in the ETACS-ECU.
  • The battery voltage is applied by the ignition switch <Vehicles without KOS> or the KOS&OSS-ECU <Vehicles with KOS> to the fuel pump relay coil (ETACS-ECU connector terminal IGS) in the ETACS-ECU. The engine-ECU turns on the relay by turning ON the power transistor in the unit so as to conduct power to the fuel pump relay coil (via the ETACS-ECU connector terminal FP/R).
  • When the fuel pump relay is turned ON, the battery voltage will be supplied from the fuel pump relay (ETACS-ECU connector terminal F/P) to the fuel pump.
 
 
FUNCTION
  • When the ignition switch ON signal is inputted into the engine-ECU, the engine-ECU turns ON the fuel pump relay. This causes the battery voltage to be supplied to the fuel pump.
 
 
PROBABLE CAUSES
  • Failed fuel pump relay in the ETACS-ECU
  • Failed fuel pump
  • Open/short circuit or harness damage in fuel pump drive circuit, or loose connector contact.
  • Failed engine-ECU
 
 
DIAGNOSIS PROCEDURE
STEP 1. Check fuel pump relay.
  • Fuel pump relay continuity check (Refer to ).
Is the check result normal?
Go to Step 2.
Replace the ETACS-ECU.
 
STEP 2. Perform voltage measurement at engine-ECU connector.
  • Disconnect connector, and measure at harness side.
  • Ignition switch: ON
  • Voltage between terminal FP/R and body earth.
OK: System voltage
Is the check result normal?
Go to Step 3.
Repair the connector(s), or check and repair of short to earth, and open circuit in FP/R line between ETACS-ECU connector and engine-ECU connector.
 
STEP 3. Perform voltage measurement at ETACS-ECU connector.
  • Disconnect connector, and measure at harness side.
  • Ignition switch: ON
  • Voltage between terminal FP/B and body earth.
OK: System voltage
Is the check result normal?
Go to Step 4.
Repair the connector(s), or check and repair of short to earth, and open circuit in FP/B line between engine control relay connector and ETACS-ECU connector.
 
STEP 4. Check fuel pump operations.
  • Fuel tank pump operation check (Refer to ).
Is the check result normal?
Go to Step 5.
Replace the fuel tank pump and gauge assembly.
 
STEP 5. Perform resistance measurement at fuel pump connector.
  • Disconnect connector, and measure at harness side.
  • Resistance between terminal earth line and body earth.
OK: Continuity (2 Ω or less)
Is the check result normal?
Go to Step 6.
Repair the connector(s), or check and repair of open circuit, and damage in earth line between fuel pump connector and body earth.
 
STEP 6. Perform voltage measurement at fuel pump connector.
  • Disconnect connector, and measure at harness side.
  • Ignition switch: ON
  • Voltage between terminal ETACS-ECU F/P line and body earth.
OK: System voltage
Is the check result normal?
Go to Step 8.
Go to Step 7.
 
STEP 7. Check of open circuit, short circuit, and damage in F/P line between ETACS-ECU connector and fuel pump connector.
Is the check result normal?
Repair the connector(s), or check and repair of damage in FP/R line between ETACS-ECU connector and engine-ECU connector.
Repair the connector(s) or wiring harness.
 
STEP 8. Check of damage in FP/B line between engine control relay connector and ETACS-ECU connector.
Is the check result normal?
Go to Step 9.
Repair the connector(s) or wiring harness.
 
STEP 9. Check of damage in F/P line between ETACS-ECU connector and fuel pump connector.
Is the check result normal?
Go to Step 10.
Repair the connector(s) or wiring harness.
 
STEP 10. M.U.T.-IIISE actuator test
  • Item 2: Fuel pump ON
OK: Operating sound of fuel pump can be heard.
Is the check result normal?
Intermittent malfunction (Refer to GROUP 00 - How to Use Troubleshooting/Inspection Service Points - How to Cope with Intermittent Malfunctions ).
Replace the engine-ECU.