PR25DD engine
|
Sensor |
Input signal to ECM |
ECM Function |
Actuator |
|
Crankshaft position sensor Camshaft position sensor |
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, 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. |
- CHECK FUEL PUMP RELAY CONTROL SIGNAL
- Turn ignition switch ON.
- Check the voltage between ECM harness connector.
ECM
Voltage
+
-
Connector
Terminal
Connector
Terminal
F90
118
F90
69
Battery voltage should exist 1 second after ignition switch is turn ON.
Is the inspection result normal?
YES
GO TO 3.
NO
GO TO 2.
- CHECK FUEL PUMP RELAY CONTROL SIGNAL CIRCUIT
- Turn ignition switch OFF.
- Disconnect ECM harness connector.
- Disconnect IPDM E/R harness connector.
- Check the continuity between ECM harness connector and IPDM E/R harness connector.
+
-
Continuity
ECM
IPDM E/R
Connector
Terminal
Connector
Terminal
F90
118
F10
76
Existed
- 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.
- CHECK FUEL PUMP POWER SUPPLY
- Turn ignition switch OFF.
- Disconnect "fuel level sensor unit and fuel pump" harness connector.
- Turn ignition switch ON.
- Check the voltage between "fuel level sensor unit and fuel pump" harness connector and ground.
+
-
Voltage
Fuel level sensor unit and fuel pump
Connector
Terminal
B42 *1
B48 *2
5
Ground
Battery voltage should exist 1 second after ignition switch is turn ON.
*1: Without all wheel drive
*2: With all wheel drive
Is the inspection result normal?
YES
GO TO 5.
NO
GO TO 4.
- CHECK FUEL PUMP POWER SUPPLY CIRCUIT
- Turn ignition switch OFF.
- Disconnect IPDM E/R harness connector.
- Check the continuity between IPDM E/R harness connector and "fuel level sensor unit and fuel pump" harness connector.
+
-
Continuity
IPDM E/R
Fuel level sensor unit and fuel pump
Connector
Terminal
Connector
Terminal
E18
46
B42 *1
B48 *2
5
Existed
*1: Without all wheel drive
*2: With all wheel drive
- 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.
- CHECK FUEL PUMP GROUND CIRCUIT
- Check the continuity between "fuel level sensor unit and fuel pump" and ground.
+
-
Continuity
Fuel level sensor unit and fuel pump
Connector
Terminal
B42 *1
B48 *2
6
Ground
Existed
*1: Without all wheel drive
*2: With all wheel drive
- Also heck harness for short to power.
Is the inspection result normal?
YES
GO TO 6.
NO
Repair or replace error-detected parts.
- Check the continuity between "fuel level sensor unit and fuel pump" and ground.
- CHECK FUEL PUMP
Refer to Component Inspection .
Is the inspection result normal?
YES
GO TO 7.
NO
Replace "fuel level sensor unit and fuel pump". Refer to Removal & Installation (AWD) or Removal & Installation (FWD).
- CHECK INTERMITTENT INCIDENT
Refer to Intermittent Incident .
Is the inspection result normal?
YES
Replace IPDM E/R. Refer to Removal & Installation .
NO
Repair or replace harness or connectors.