Fuel Pump: Testing and Inspection

FUEL PUMP





Description

SYSTEM DESCRIPTION





The ECM activates the fuel pump for several seconds after the ignition switch is turned ON to improve engine start ability. If the ECM receives a engine speed signal from the crankshaft position sensor (POS) and camshaft position sensor (PHASE), it knows that the engine is rotating, and causes the pump to operate. If the engine speed signal is not received when the ignition switch is ON, the engine stalls. The ECM stops pump operation and prevents battery discharging, thereby improving safety. The ECM does not directly drive the fuel pump. It controls the ON/OFF fuel pump relay, which in turn controls the fuel pump.






COMPONENT DESCRIPTION





A turbine type design fuel pump is used in the fuel tank.
- Fuel level sensor unit and fuel pump (1)
- Fuel pressure regulator (2)
- Fuel level sensor (3)
- Fuel tank temperature sensor (4)




CONSULT-III Reference Value in Data Monitor Mode
Specification data are reference values.









Wiring Diagram





Specification data are reference values and are measured between each terminal and ground.

CAUTION:
Do not use ECM ground terminals when measuring input/output voltage. Doing so may result in damage to the ECM's transistor. Use a ground other than ECM terminals, such as the ground.









Diagnosis Procedure
1.CHECK OVERALL FUNCTION
1. Turn ignition switch ON.





2. Pinch fuel feed hose (1) with two fingers.
- Illustration shows the view with intake air duct removed.





OK or NG
OK - INSPECTION END
NG - GO TO 2.
2.CHECK FUEL PUMP POWER SUPPLY CIRCUIT-I
1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
3. Turn ignition switch ON.





4. Check voltage between ECM terminal 23 and ground with CONSULT-III or tester.





OK or NG
OK - GO TO 5.
NG - GO TO 3.
3.CHECK FUEL PUMP POWER SUPPLY CIRCUIT-II
1. Turn ignition switch OFF.
2. Disconnect IPDM E/R harness connector E46.
3. Turn ignition switch ON.





4. Check voltage between IPDM E/R terminal 47 and ground with
CONSULT-III or tester.





OK or NG
OK - GO TO 4.
NG - GO TO 11.
4.DETECT MALFUNCTIONING PART
Check the following.
- Harness connectors E8, F8
- Harness for open or short between IPDM E/R and ECM
- Repair open circuit or short to ground or short to power in harness or connectors.
5.CHECK FUEL PUMP POWER SUPPLY CIRCUIT-III
1. Turn ignition switch OFF.
2. Reconnect all harness connectors disconnected.





3. Disconnect "fuel level sensor unit and fuel pump" harness connector (1).
- Illustration shows the view with inspection hole cover removed.
4. Turn ignition switch ON.





5. Check voltage between "fuel level sensor unit and fuel pump" terminal 1 and ground with CONSULT-III or tester.





OK or NG
OK - GO TO 9.
NG - GO TO 6.
6.CHECK 15 A FUSE
1. Turn ignition switch OFF.
2. Disconnect 15 A fuse.
3. Check 15 A fuse.
OK or NG
OK - GO TO 7.
NG - Replace fuse.
7.CHECK FUEL PUMP POWER SUPPLY CIRCUIT-IV
1. Disconnect IPDM E/R harness connector E45.
2. Check harness continuity between IPDM E/R terminal 36 and "fuel level sensor unit and fuel pump" terminal 1. Refer to Wiring Diagram.





3. Also check harness for short to ground and short to power.
OK or NG
OK - GO TO 11.
NG - GO TO 8.
8.DETECT MALFUNCTIONING PART
Check the following.
- Harness connectors M69, E7
- Harness connectors M12, B101
- Harness for open or short between IPDM E/R and "fuel level sensor unit and fuel pump"
- Repair open circuit or short to ground or short to power in harness or connectors.
9.CHECK FUEL PUMP GROUND CIRCUIT
1. Check harness continuity between "fuel level sensor unit and fuel pump" terminal 3 and ground. Refer to Wiring Diagram.





2. Also check harness for short to power.
OK or NG
OK - GO TO 10.
NG - Repair or replace harness or connectors.
10.CHECK FUEL PUMP
SEE Component Inspection.
OK or NG
OK - GO TO 11.
NG - Replace fuel pump.
11.CHECK INTERMITTENT INCIDENT
Trouble Diagnosis For Intermittent Incident Trouble Diagnosis For Intermittent Incident.
OK or NG
OK - Replace IPDM E/R. Service and Repair.
NG - Repair or replace harness or connectors.




Component Inspection

FUEL PUMP
1. Disconnect "fuel level sensor unit and fuel pump" harness connector.





2. Check resistance between "fuel level sensor unit and fuel pump" terminals 1 and 3.





3. If NG, replace "fuel level sensor unit and fuel pump".




Removal and Installation

FUEL PUMP
Removal and Installation.