Description
| Sensor | Input signal to ECM | ECM Function | Actuator |
| Crankshaft position sensor (POS) Camshaft position sensor (PHASE) |
Engine speed* | Fuel pump control | Fuel pump relay ↓ Fuel pump |
| Battery | Battery voltage* |
*: ECM determines the start signal status by the signals of engine speed and battery voltage.
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 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.
| Condition | Fuel pump operation |
| Ignition switch is turned to ON | Operates for 1 second. |
| Engine running and cranking | Operates. |
| When engine is stopped | Stops in 1.5 seconds. |
| Except as shown above | Stops. |
Component Function Check
1.CHECK FUEL PUMP FUNCTION
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 >> Proceed to EC-467, "Diagnosis Procedure".
Diagnosis Procedure
1.CHECK FUEL PUMP RELAY CONTROL SIGNAL

Is the inspection result normal? YES >> GO TO 3.
NO >> GO TO 2.
2.CHECK FUEL PUMP RELAY CONTROL SIGNAL CIRCUIT

Also check harness for short to ground and to power.
Is the inspection result normal? YES >> GO TO 7.
NO >> Repair or replace error-detected parts.
3.CHECK FUEL PUMP POWER SUPPLY

Is the inspection result normal? YES >> GO TO 5.
NO >> GO TO 4.
4.CHECK FUEL PUMP POWER SUPPLY CIRCUIT

Is the inspection result normal? YES >> GO TO 7.
NO >> Repair or replace error-detected parts.
5.CHECK FUEL PUMP GROUND CIRCUIT

Is the inspection result normal?
YES >> GO TO 6.
NO >> Repair or replace error-detected parts.
6.CHECK FUEL PUMP
Refer to EC-469, "Component Inspection".
Is the inspection result normal? YES >> GO TO 7.
NO >> Replace “fuel level sensor unit and fuel pump”. Refer to FL-6, "Removal and Installation".
7.CHECK INTERMITTENT INCIDENT
Perform GI-41, "Intermittent Incident".
Is the inspection result normal? YES >> Replace IPDM E/R. Refer to PCS-35, "Removal and Installation".
NO >> Repair or replace harness or connectors.
Component Inspection
1.CHECK FUEL PUMP

Is the inspection result normal? YES >> INSPECTION END
NO >> Replace “fuel level sensor unit and fuel pump”. Refer to FL-6, "Removal and Installation".
Fuel injector
Ignition signalSymptom diagnosis
EXTERIOR LIGHTING SYSTEM SYMPTOMS
Symptom Table
CAUTION:
Perform the self-diagnosis with CONSULT before the symptom diagnosis. Perform
the trouble diagnosis
if any DTC is detected.
NORMAL OPERATING CONDITION
Description
AUTO LIGHT SYSTEM
The headlamp may not be turned ON/OFF immedi ...
Refrigeration system symptoms
Trouble Diagnosis For Unusual Pressure
Diagnose using a manifold gauge whenever system’s high and/or low side
pressure(s) is/are unusual. The
marker above the gauge scale in the following tables indicates the standard
(usual) pressure range. Refer to
above table (Ambient air temperature-to- ...
Symptom diagnosi
NOISE, VIBRATION, AND HARSHNESS (NVH) TROUBLESHOOTING
NVH troubleshooting - engine noise
Valve mechanism
Intake and exhaust valve
Water pump
Timing chain
Drive belt
Rotation mechanism
Tappet noise
Camshaft bearing noise
&nb ...