DESCRIPTION
The fuel pump circuit consists of the ECM, fuel pump and fuel pump control ECU assembly (which operates the fuel pump). Based on the engine output, the ECM determines the fuel pump speed. The speed is then converted to a duty signal and sent to the fuel pump control ECU assembly. Based on the signal sent from the ECM, the fuel pump ECU adjust the fuel pump operation speed.
When the engine is cranked, the ST (starter) relay drive signal output from the ignition switch assembly*1 or certification ECU (smart key ECU assembly)*2 is input into the STA terminal of the ECM, and the NE signal generated by the crankshaft position sensor is also input into the NE+ terminal. The ECM interprets that the engine is cranked, and turns transistor Tr1 in the ECM internal circuit on. Current flows to the C/OPN (Circuit Opening) relay by turning Tr1 on. Then, the fuel pump operates.
While the NE signal is input into the ECM with the engine running, the ECM turns Tr1 on continuously.
*1: w/o Entry and Start System
*2: w/ Entry and Start System
WIRING DIAGRAM
CAUTION / NOTICE / HINT
Note
Inspect the fuses for circuits related to this system before performing the following procedure.
PROCEDURE
PERFORM ACTIVE TEST USING GTS (CONTROL THE FUEL PUMP / SPEED)
Connect the GTS to the DLC3.
Turn the ignition switch to ON.
Turn the GTS on.
Enter the following menus: Powertrain / Engine and ECT / Active Test / Control the Fuel Pump / Speed.
w/ Fuel Pump Control ECU Assembly
| Tester Display |
|---|
| Control the Fuel Pump / Speed |
w/o Fuel Pump Control ECU Assembly
| Tester Display |
|---|
| Control the Fuel Pump / Speed |
Check whether the fuel pump operating sound occurs when performing the Active Test on the GTS.
| Result | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|
|
| B |
|
CHECK TERMINAL VOLTAGE (POWER SOURCE OF C/OPN RELAY) Click here |
| C |
|
PERFORM ACTIVE TEST USING GTS (CONTROL THE FUEL PUMP DUTY) Click here |
| D |
|
READ VALUE USING GTS (STARTER SIGNAL) Click here |
| A |
|
CHECK TERMINAL VOLTAGE (POWER SOURCE OF FUEL PUMP CONTROL ECU ASSEMBLY)
| *a | Front view of wire harness connector (to Fuel Pump Control ECU Assembly) |
Disconnect the fuel pump control ECU Assembly connector.
Turn the ignition switch to ON.
Measure the voltage according to the value(s) in the table below.
| Standard Voltage | ||||||
|---|---|---|---|---|---|---|
|
| Result | |||
|---|---|---|---|
|
| NG |
|
CHECK HARNESS AND CONNECTOR (EFI-MAIN NO. 2 RELAY - FUEL PUMP CONTROL ECU ASSEMBLY) Click here |
| OK |
|
CHECK HARNESS AND CONNECTOR (FUEL PUMP CONTROL ECU ASSEMBLY - BODY GROUND)
Disconnect the fuel pump control ECU assembly connector.
Measure the resistance according to the value(s) in the table below.
| Standard Resistance | ||||||
|---|---|---|---|---|---|---|
|
| Result | |||
|---|---|---|---|
|
| NG |
|
REPAIR OR REPLACE HARNESS OR CONNECTOR |
| OK |
|
CHECK HARNESS AND CONNECTOR (FUEL PUMP - FUEL PUMP CONTROL ECU ASSEMBLY)
Disconnect the fuel pump control ECU assembly connector.
Disconnect the fuel pump connector.
Measure the resistance according to the value(s) in the table below.
| Standard Resistance | |||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
|
| Result | |||
|---|---|---|---|
|
| NG |
|
REPAIR OR REPLACE HARNESS OR CONNECTOR |
| OK |
|
INSPECT FUEL PUMP
Inspect fuel pump.
| Result | |||
|---|---|---|---|
|
| NG |
|
REPLACE FUEL PUMP Click here |
| OK |
|
CHECK HARNESS AND CONNECTOR (FUEL PUMP CONTROL ECU ASSEMBLY - ECM)
Disconnect the fuel pump control ECU assembly connector.
Disconnect the ECM connector.
Measure the resistance according to the value(s) in the table below.
| Standard Resistance | |||||||||
|---|---|---|---|---|---|---|---|---|---|
|
| Result | |||
|---|---|---|---|
|
| NG |
|
REPAIR OR REPLACE HARNESS OR CONNECTOR |
| OK |
|
REPLACE FUEL PUMP CONTROL ECU ASSEMBLY
Replace the fuel pump control ECU assembly.
| Result | ||
|---|---|---|
|
| NEXT |
|
CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIRED
Check the fuel pump operation.
| OK |
|---|
| Malfunction has been repaired successfully. |
| Result | |||
|---|---|---|---|
|
| OK |
|
END |
| NG |
|
REPLACE ECM Click here |
CHECK HARNESS AND CONNECTOR (EFI-MAIN NO. 2 RELAY - FUEL PUMP CONTROL ECU ASSEMBLY)
Remove the EFI-MAIN NO. 2 relay from the engine room relay block and junction block assembly.
Disconnect the fuel pump control ECU assembly connector.
Measure the resistance according to the value(s) in the table below.
| Standard Resistance | |||||||||
|---|---|---|---|---|---|---|---|---|---|
|
| Result | |||
|---|---|---|---|
|
| OK |
|
GO TO ECM POWER SOURCE CIRCUIT Click here |
| NG |
|
REPAIR OR REPLACE HARNESS OR CONNECTOR |
CHECK TERMINAL VOLTAGE (POWER SOURCE OF C/OPN RELAY)
| *1 | Engine Room Relay Block and Junction Block Assembly |
| *2 | C/OPN Relay |
Remove the C/OPN relay from the engine room relay block and junction block assembly.
Turn the ignition switch to ON.
Measure the voltage according to the value(s) in the table below.
| Standard Voltage | ||||||
|---|---|---|---|---|---|---|
|
| Result | |||
|---|---|---|---|
|
| NG |
|
CHECK HARNESS AND CONNECTOR (C/OPN RELAY - IG2 RELAY) Click here |
| OK |
|
INSPECT C/OPN RELAY
Inspect the C/OPN relay.
| Result | |||
|---|---|---|---|
|
| NG |
|
REPLACE C/OPN RELAY |
| OK |
|
CHECK HARNESS AND CONNECTOR (C/OPN RELAY - ECM)
Remove the C/OPN relay from the engine room relay block and junction block assembly.
Disconnect the ECM connector.
Measure the resistance according to the value(s) in the table below.
| Standard Resistance | |||||||||
|---|---|---|---|---|---|---|---|---|---|
|
| Result | |||
|---|---|---|---|
|
| NG |
|
REPAIR OR REPLACE HARNESS OR CONNECTOR |
| OK |
|
CHECK HARNESS AND CONNECTOR (C/OPN RELAY - FUEL PUMP)
Remove the C/OPN relay from the engine room relay block and junction block assembly.
Disconnect the fuel pump connector.
Measure the resistance according to the value(s) in the table below.
| Standard Resistance | |||||||||
|---|---|---|---|---|---|---|---|---|---|
|
| Result | |||
|---|---|---|---|
|
| NG |
|
REPAIR OR REPLACE HARNESS OR CONNECTOR |
| OK |
|
CHECK HARNESS AND CONNECTOR (FUEL PUMP - BODY GROUND)
Disconnect the fuel pump connector.
Measure the resistance according to the value(s) in the table below.
| Standard Resistance | ||||||
|---|---|---|---|---|---|---|
|
| Result | |||
|---|---|---|---|
|
| NG |
|
REPAIR OR REPLACE HARNESS OR CONNECTOR |
| OK |
|
INSPECT FUEL PUMP
Inspect fuel pump.
| Result | |||
|---|---|---|---|
|
| NG |
|
REPLACE FUEL PUMP Click here |
| OK |
|
CHECK HARNESS AND CONNECTOR (C/OPN RELAY - EFI-MAIN NO. 2 RELAY)
Remove the C/OPN relay and EFI-MAIN NO. 2 relay from the engine room relay block and junction block assembly.
Measure the resistance according to the value(s) in the table below.
| Standard Resistance | |||||||||
|---|---|---|---|---|---|---|---|---|---|
|
| Result | |||
|---|---|---|---|
|
| OK |
|
GO TO ECM POWER SOURCE CIRCUIT Click here |
| NG |
|
REPAIR OR REPLACE HARNESS OR CONNECTOR |
CHECK HARNESS AND CONNECTOR (C/OPN RELAY - IG2 RELAY)
Remove the C/OPN relay and IG2 relay from the engine room relay block and junction block assembly.
Measure the resistance according to the value(s) in the table below.
| Standard Resistance | |||||||||
|---|---|---|---|---|---|---|---|---|---|
|
| Result | |||
|---|---|---|---|
|
| OK |
|
GO TO ECM POWER SOURCE CIRCUIT Click here |
| NG |
|
REPAIR OR REPLACE HARNESS OR CONNECTOR |
PERFORM ACTIVE TEST USING GTS (CONTROL THE FUEL PUMP DUTY)
Remove the fuel suction with pump and gauge tube assembly.
Clean the fuel suction with pump and gauge tube assembly to completely remove any remaining fuel.
Remove the fuel pump.
Connect the fuel pump and fuel suction with pump and gauge tube assembly connector.
Note
Confirm that no fuel remains inside or on the outside of the fuel pump.
Connect the GTS to the DLC3.
Turn the ignition switch to ON.
Turn the GTS on.
Enter the following menus: Powertrain / Engine and ECT / Active Test / Control the Fuel Pump Duty.
| Tester Display |
|---|
| Control the Fuel Pump Duty |
| *a | Component with harness connected (Fuel Pump) |
Operate the fuel pump using the Active Test function and measure the voltage according to the value(s) in the table below.
| Standard Voltage | ||||||||
|---|---|---|---|---|---|---|---|---|
|
Enter the following menus: Powertrain / Engine and ECT / Active Test / Control the Fuel Pump / Speed.
| Tester Display |
|---|
| Control the Fuel Pump / Speed |
Operate the fuel pump using the Active Test function and measure the voltage according to the value(s) in the table below.
| Standard Voltage | ||||||
|---|---|---|---|---|---|---|
|
Tech Tips
Be sure to measure the voltage with all the connectors connected.
Before performing this inspection, check that the battery voltage is between 11 and 14 V (not depleted).
| Result | |||
|---|---|---|---|
|
| NG |
|
REPLACE FUEL PUMP CONTROL ECU ASSEMBLY Click here |
| OK |
|
CHECK HARNESS AND CONNECTOR (FUEL PUMP CONTROL ECU ASSEMBLY - ECM)
Disconnect the fuel pump control ECU assembly connector.
Disconnect the ECM connector.
Measure the resistance according to the value(s) in the table below.
| Standard Resistance | |||||||||
|---|---|---|---|---|---|---|---|---|---|
|
| Result | |||
|---|---|---|---|
|
| NG |
|
REPAIR OR REPLACE HARNESS OR CONNECTOR |
| OK |
|
REPLACE FUEL PUMP
Replace the fuel pump.
| Result | ||
|---|---|---|
|
| NEXT |
|
CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIRED
Check the fuel pump operation.
| OK |
|---|
| Malfunction has been repaired successfully. |
| Result | |||
|---|---|---|---|
|
| OK |
|
END |
| NG |
|
REPLACE ECM Click here |
REPLACE FUEL PUMP CONTROL ECU ASSEMBLY
Replace the fuel pump control ECU assembly.
| Result | ||
|---|---|---|
|
| NEXT |
|
GO TO STEP 21 Click here |
READ VALUE USING GTS (STARTER SIGNAL)
Connect the GTS to the DLC3.
Turn the ignition switch to ON.
Turn the GTS on.
Enter the following menus: Powertrain / Engine and ECT / Data List / All Data / Starter Signal.
| Tester Display |
|---|
| Starter Signal |
Check the result when the ignition switch is ON and the engine starts.
| OK | ||||||
|---|---|---|---|---|---|---|
|
| Result | |||
|---|---|---|---|
|
| NG |
|
CHECK STARTER SIGNAL CIRCUIT Click here |
| OK |
|
READ VALUE USING GTS (ENGINE SPEED)
Connect the GTS to the DLC3.
Turn the ignition switch to ON.
Turn the GTS on.
Enter the following menus: Powertrain / Engine and ECT / Data List / All Data / Engine Speed.
| Tester Display |
|---|
| Engine Speed |
Read the values displayed on the GTS while cranking.
| OK |
|---|
| Values are displayed continuously. |
| Result | |||
|---|---|---|---|
|
| OK |
|
PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE Click here |
| NG |
|
CHECK CRANKSHAFT POSITION SENSOR CIRCUIT Click here |