Sfi System - Fuel Pump Control Circuit
Lexus IS250 IS220d GSE20 ALE20 4GR-FSE ENGINE CONTROL SYSTEM
DESCRIPTION
WIRING DIAGRAM
INSPECTION PROCEDURE
CHECK FUEL PUMP (FUEL PUMP OPERATION)
PERFORM ACTIVE TEST BY INTELLIGENT TESTER (OPERATE CIRCUIT OPENING RELAY)
INSPECT ECM POWER SOURCE CIRCUIT
INSPECT FUSE (F/PMP FUSE)
INSPECT INTEGRATION RELAY (EFI NO. 2 RELAY)
INSPECT INTEGRATION RELAY (C/OPN RELAY)
INSPECT ECM (FC VOLTAGE)
INSPECT F/PMP RELAY
INSPECT FUEL PUMP
CHECK HARNESS AND CONNECTOR (FUEL PUMP - F/PMP RELAY)
CHECK HARNESS AND CONNECTOR (INTEGRATION RELAY - F/PMP RELAY)
INSPECT F/PMP RELAY
INSPECT FUEL PUMP RESISTER
CHECK HARNESS AND CONNECTOR (F/PMP RELAY - FUEL PUMP RESISTER)
SFI SYSTEM - Fuel Pump Control Circuit
DESCRIPTION
Refer to DTC P0230 .
WIRING DIAGRAM
Refer to DTC P0230 .
INSPECTION PROCEDURE
| 1.CHECK FUEL PUMP (FUEL PUMP OPERATION) |
Check if there is pressure in the fuel inlet hose.
- If there is fuel pressure, you will hear the sound of fuel flowing.
| 2.PERFORM ACTIVE TEST BY INTELLIGENT TESTER (OPERATE CIRCUIT OPENING RELAY) |
Connect the intelligent tester to the DLC3.
Turn the engine switch on (IG) and turn the intelligent tester ON.
Enter the following menus: Power train / Engine / Active Test / Control the Fuel Pump / Speed.
Check the operation of the relay while operating it using the intelligent tester.
- OK:
- Operating noise can be heard from the relay.
| 3.INSPECT ECM POWER SOURCE CIRCUIT |
| | REPAIR OR REPLACE POWER SOURCE CIRCUIT |
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| 4.INSPECT FUSE (F/PMP FUSE) |
Remove the F/PMP fuse from the engine room J/B and R/B No. 2.
Measure the resistance of the F/PMP fuse.
- Standard resistance:
- Below 1 Ω
| 5.INSPECT INTEGRATION RELAY (EFI NO. 2 RELAY) |
Remove the integration relay from the engine room J/B and R/B No. 2.
Measure the resistance of the EFI No. 2 relay.
- Standard resistance:
| Tester Connection | Specified Condition |
| 2B-4 - 2C-1 | 10 kΩ or higher |
| 2B-4 - 2C-1 | Below 1 Ω
(when battery voltage applied to terminals 2B-3 and 2B-2) |
| | REPLACE INTEGRATION RELAY |
|
|
| 6.INSPECT INTEGRATION RELAY (C/OPN RELAY) |
Remove the integration relay from the engine room J/B and R/B No. 2.
Measure the resistance of the C/OPN relay.
- Standard resistance:
| Tester Connection | Specified Condition |
| 2B-6 - 2B-8 | 10 kΩ or higher |
| 2B-6 - 2B-8 | Below 1 Ω
(when battery voltage applied to terminals 2B-6 and 2B-7) |
| | REPLACE INTEGRATION RELAY |
|
|
| 7.INSPECT ECM (FC VOLTAGE) |
Turn the engine switch on (IG).
Measure the voltage of the A5 and E4 ECM connectors.
- Standard voltage:
| Tester Connection | Specified Condition |
| FC (A5-14) - E1 (E4-7) | 9 to 14 V |
| NG | |
| |
| CHECK AND REPAIR HARNESS AND CONNECTOR (ECM - CIRCUIT OPENING RELAY) |
|
Remove the F/PMP relay from the engine room J/B and R/B No. 2.
Measure the resistance of the F/PMP relay.
- Standard resistance:
| Tester Connection | Specified Condition |
| 3 - 4 | 10 kΩ or higher |
| 3 - 4 | Below 1 Ω
(when battery voltage applied to terminals 1 and 2) |
Inspect fuel pump resistance.
Measure the resistance between terminals 4 and 5.
- Standard resistance:
- 0.2 to 3.0 Ω at 20°C (68°F)
Inspect fuel pump operation.
Apply battery voltage to both the terminals. Check that the pump operates.
These tests must be done quickly (within 10 seconds) to prevent the coil from burning out.
Keep fuel pump as far away from the battery as possible.
Always switch at the battery side.
| 10.CHECK HARNESS AND CONNECTOR (FUEL PUMP - F/PMP RELAY) |
Check the harness and the connectors between the fuel pump and the F/PMP relay.
Disconnect the fuel pump connector.
Remove the F/PMP relay from the engine room J/B and R/B No. 2.
Measure the resistance of the wire harness side connectors.
- Standard resistance (Check for open):
| Tester Connection | Specified Condition |
| Fuel pump (Q14-4) - F/PMP relay (4) | Below 1 Ω |
- Standard resistance (Check for short):
| Tester Connection | Specified Condition |
| Fuel pump (Q14-4) or F/PMP (4) - Body ground | 10 kΩ or higher |
Check the harness and the connectors between the fuel pump and the body ground.
Disconnect the fuel pump connector.
Measure the resistance of the wire harness side connector and the body ground.
- Standard resistance (Check for open):
| Tester Connection | Specified Condition |
| Fuel pump (Q14-5) - Body ground | 10 kΩ or higher |
| | REPAIR OR REPLACE HARNESS OR CONNECTOR |
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| 11.CHECK HARNESS AND CONNECTOR (INTEGRATION RELAY - F/PMP RELAY) |
Remove the integration relay from the engine room J/B and R/B No. 2.
Remove the F/PMP relay from the engine room J/B and R/B No. 2.
Measure the resistance of the wire harness side connectors.
- Standard resistance (Check for open):
| Tester Connection | Specified Condition |
| Integration relay (2B-8) - F/PMP relay (1) | Below 1 Ω |
| Integration relay (2B-8) - F/PMP relay (3) | Below 1 Ω |
- Standard resistance (Check for short):
| Tester Connection | Specified Condition |
| Circuit opening relay (2B-8) or F/PMP relay (1) - Body ground | 10 kΩ or higher |
| Circuit opening relay (2B-8) or F/PMP relay (3) - Body ground | 10 kΩ or higher |
| | REPAIR OR REPLACE HARNESS OR CONNECTOR |
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| OK | |
| |
| REPAIR OR REPLACE INTEGRATION RELAY |
|
Remove the F/PMP relay from the engine room J/B and R/B No. 2.
Measure the resistance of the F/PMP relay.
- Standard resistance:
| Tester Connection | Specified Condition |
| 3 - 4 | 10 kΩ or higher |
| 3 - 4 | Below 1 Ω
(when battery voltage applied to terminals 1 and 2) |
| 13.INSPECT FUEL PUMP RESISTER |
Measure the resistance of the fuel pump resistor.
- Standard resistance:
- 0.30 to 0.34 Ω at 20°C (68°F)
| | REPLACE FUEL PUMP RESISTER |
|
|
| 14.CHECK HARNESS AND CONNECTOR (F/PMP RELAY - FUEL PUMP RESISTER) |
Check the harness and the connectors between the F/PMP relay and the fuel pump resistor.
Remove the F/PMP relay from the engine room J/B and R/B No. 2.
Disconnect the fuel pump resistor connector.
Measure the resistance of the wire harness side connectors.
- Standard resistance (Check for open):
| Tester Connection | Specified Condition |
| F/PMP relay (4) - Fuel pump resistor (A40-2) | Below 1 Ω |
| F/PMP relay (3) - Fuel pump resistor (A40-1) | Below 1 Ω |
- Standard resistance (Check for short):
| Tester Connection | Specified Condition |
| Fuel pump relay (4) or Fuel pump resistor (A40-2) - Body ground | 10 kΩ or higher |
| Fuel pump relay (4) or Fuel pump resistor (A40-1) - Body ground | 10 kΩ or higher |
| | PROCEED TO NEXT INSPECTION PROCEDURE SHOWN IN PROBLEM SYMPTOMS TABLE |
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| NG | |
| |
| REPAIR OR REPLACE HARNESS OR CONNECTOR |
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LEXUS IS250, IS220d / GSE20 ALE20
