Component Test

FUEL PUMP

Description






The ECM activates the fuel pump for several seconds after the ignition switch is turned ON to improve engine startability. If the ECM receives a engine speed signal from the 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 Function Check


1. CHECK FUEL PUMP FUNCTION

1.Turn ignition switch ON.





2.Pinch fuel feed hose (1) with two fingers.





Fuel pressure pulsation should be felt on the fuel feed
hose for 1 second after ignition switch is turned ON.
Is the inspection result normal?
YES- INSPECTION END
NO-.


Diagnosis Procedure


1. CHECK FUEL PUMP POWER SUPPLY CIRCUIT-I

1.Turn ignition switch OFF.
2.Disconnect ECM harness connector.
3.Turn ignition switch ON.
4.Check the voltage between ECM harness connector and ground.





Is the inspection result normal?
YES- GO TO 4.
NO- GO TO 2.

2. CHECK FUEL PUMP POWER SUPPLY CIRCUIT-II

1.Turn ignition switch OFF.
2.Disconnect IPDM E/R harness connector E13.
3.Check the continuity between IPDM E/R harness connector and ECM harness connector.





Is the inspection result normal?
YES- GO TO 9.
NO- GO TO 3.

3. DETECT MALFUNCTIONING PART

Check the following.
- Harness connectors E6, F123
- IPDM E/R connector E13
- Harness for open or short between ECM and IPDM E/R
- Repair open circuit or short to ground or short to power in harness or connectors.

4. CHECK 15 A FUSE

1.Disconnect 15 A fuse (No. 57) from IPDM E/R.
2.Check 15 A fuse. For the fuse number, Except For Mexico. For the fuse arrangement, IPDM E/R.
Is the inspection result normal?
YES- GO TO 5.
NO- Replace fuse.

5. CHECK FUEL PUMP POWER SUPPLY CIRCUIT-III

1.Disconnect "fuel level sensor unit and fuel pump" harness connector.
2.Check the continuity between IPDM E/R harness connector and "fuel level sensor unit and fuel pump" and ground.





Is the inspection result normal?
YES- GO TO 7.
NO- GO TO 6.

6. DETECT MALFUNCTIONING PART

Check the following.
- Harness connectors E105, M77
- Harness connectors M11, B1
- Harness for open or short between "fuel level sensor unit and fuel pump" and IPDM E/R
- Repair open circuit or short to ground or short to power in harness or connectors.

7. CHECK FUEL PUMP GROUND CIRCUIT

1.Check the continuity between "fuel level sensor unit and fuel pump" and ground.





2.Also heck harness for short to power.
Is the inspection result normal?
YES- GO TO 8.
NO- Repair open circuit or short to power in harness or connectors.

8. CHECK FUEL PUMP

.
Is the inspection result normal?
YES- GO TO 9.
NO- Replace fuel pump. Type 1 Removal And Installation (2WD models) or Type 1 Removal And Installation (AWD models).

9. CHECK INTERMITTENT INCIDENT

Intermittent Incident.
Is the inspection result normal?
YES- Replace IPDM E/R. Removal And Installation.
NO- Repair or replace harness or connectors.


Component Inspection


1. CHECK FUEL PUMP

1.Turn ignition switch OFF.
2.Disconnect "fuel level sensor unit and fuel pump" harness connector.
3.Check resistance between "fuel level sensor unit and fuel pump" terminals as follows.





Is the inspection result normal?
YES- INSPECTION END
NO- Replace "fuel level sensor unit and fuel pump". Type 1 Removal And Installation
(2WD models) or Type 1 Removal And Installation (AWD models).