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".
DTC/circuit diagnosis
U1000 CAN COMM CIRCUIT
Description
CAN (Controller Area Network) is a serial communication system for real time
application. It is an on-vehicle
multiplex communication system with high data communication speed and excellent
error detection ability.
Many electronic control units are equipp ...
ECU diagnosis information
AV CONTROL UNIT
Reference Value
VALUES ON THE DIAGNOSIS TOOL
TERMINAL LAYOUT
PHYSICAL VALUES
DTC Index
BOSE SPEAKER AMP
Reference Value
TERMINAL LAYOUT
PHYSICAL VALUES
AROUND VIEW MONITOR CONTROL UNIT
WITHOUT DRIVER ASSISTANCE SYSTEM
WITHOUT DRIV ...
Consult/gst checking system
Description
NOTE:
This vehicle is diagnosed using the CONSULT-III plus.
When CONSULT is connected with a data link connector equipped
on the vehicle side, it will communicate with the control unit
equipped in the vehicle and then enable various kinds of diagnostic
tests.
Ho ...