Fuel Pump Control Circuit

1GR-FE ENGINE CONTROL SYSTEM: SFI SYSTEM: Fuel Pump Control Circuit
- Fuel Pump Control Circuit

DESCRIPTION

Refer to DTC P0230 P0230.

WIRING DIAGRAM





INSPECTION PROCEDURE

NOTICE:
Inspection the fuses for circuits related to this system before performing the following inspection procedure.

PROCEDURE

1. CHECK FUEL PUMP OPERATION

(a) Check if there is pressure in the fuel inlet hose.

HINT
If there is fuel pressure, you will hear the sound of fuel flowing.

NG -- PERFORM ACTIVE TEST USING TECHSTREAM (OPERATE CIRCUIT OPENING RELAY)
OK -- Continue to next step.

2. INSPECT FUEL PUMP RELAY

(a) Inspect the fuel pump relay Fuel Pump Relay.

NG -- REPLACE FUEL PUMP RELAY
OK -- Continue to next step.

3. INSPECT FUEL PUMP RESISTOR (RESISTANCE)





(a) Disconnect the fuel pump resistor connector.

(b) Measure the resistance according to the value(s) in the table below.

Standard Resistance:





Text in Illustration





NG -- REPLACE FUEL PUMP RESISTOR
OK -- Continue to next step.

4. CHECK HARNESS AND CONNECTOR (FUEL PUMP RELAY - FUEL PUMP RESISTOR - FUEL PUMP)

(a) Check the harness and connector between the fuel pump relay and fuel pump resistor.

(1) Remove the fuel pump relay from the engine room relay block.

(2) Disconnect the fuel pump resistor connector.

(3) Measure the resistance according to the value(s) in the table below.

Standard Resistance:





(b) Check the harness and connector between the fuel pump resistor and fuel pump.

(1) Disconnect the fuel pump resistor connector.

(2) Disconnect the fuel pump connector.

(3) Measure the resistance according to the value(s) in the table below.

Standard Resistance:





NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR

OK -- PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE Symptom Related Diagnostic Procedures

5. PERFORM ACTIVE TEST USING TECHSTREAM (OPERATE CIRCUIT OPENING RELAY)

(a) Connect the Techstream to the DLC3.

(b) Turn the ignition switch to ON and turn the Techstream on.

(c) Enter the following menus: Powertrain / Engine and ECT / Active Test / Control the Fuel Pump/Speed.

(d) Check whether operating sounds can be heard while operating the relay using the Techstream.

OK:

Operating sounds can be heard from relay.

NG -- INSPECT C/OPN RELAY
OK -- Continue to next step.

6. CHECK ECM POWER SOURCE CIRCUIT

(a) Check the ECM power source circuit.

HINT
Refer to ECM Power Source Circuit ECM Power Source Circuit.

NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- Continue to next step.

7. INSPECT FUEL PUMP RELAY

(a) Inspect the fuel pump relay Fuel Pump Relay.

NG -- REPLACE FUEL PUMP RELAY
OK -- Continue to next step.

8. INSPECT FUEL PUMP





(a) Inspect the fuel pump resistance.

(1) Measure the resistance according to the value(s) in the table below.

Standard Resistance:





Text in Illustration





(b) Inspect the fuel pump operation.

(1) Apply battery voltage to both terminals. Check that the pump operates.

CAUTION:
* These tests must be done quickly (within 10 seconds) to prevent the coil from burning out.
* Keep the fuel pump as far away from the battery as possible.
* Always do the switching at the battery side.
NG -- REPLACE FUEL PUMP Removal
OK -- Continue to next step.

9. CHECK HARNESS AND CONNECTOR (FUEL PUMP - FUEL PUMP RELAY, FUEL PUMP - BODY GROUND)

(a) Check the harness and connector between the fuel pump and fuel pump relay.

(1) Disconnect the fuel pump connector.

(2) Remove the fuel pump relay from the engine room relay block.

(3) Measure the resistance according to the value(s) in the table below.

Standard Resistance:





(b) Check the harness and connector between the fuel pump and body ground.

(1) Disconnect the fuel pump connector.

(2) Measure the resistance according to the value(s) in the table below.

Standard Resistance:





NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- Continue to next step.

10. CHECK HARNESS AND CONNECTOR (C/OPN RELAY - FUEL PUMP RELAY)

(a) Remove the C/OPN relay from the engine room relay block.

(b) Remove the fuel pump relay from the engine room relay block.

(c) Measure the resistance according to the value(s) in the table below.

Standard Resistance:





NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR

OK -- CHECK AND REPAIR HARNESS OR CONNECTOR (EFI RELAY - CIRCUIT OPENING RELAY)

11. INSPECT C/OPN RELAY

(a) Inspect the C/OPN relay Testing and Inspection.

NG -- REPLACE C/OPN RELAY
OK -- Continue to next step.

12. INSPECT ECM (FC VOLTAGE)





(a) Turn the ignition switch to ON.

(b) Measure the voltage according to the value(s) in the table below.

Standard Voltage:





Text in Illustration





NG -- CHECK AND REPLACE HARNESS OR CONNECTOR (ECM - CIRCUIT OPENING RELAY - IGNITION SWITCH)

OK -- REPLACE ECM Removal