Toyota Camry (XV70): Fuel Pump Control Circuit

DESCRIPTION

The fuel pump (for low pressure side) circuit consists of the ECM, fuel pump (for low pressure side) and fuel pump control ECU (which operates the fuel pump (for low pressure side)). 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. Based on the signal sent from the ECM, the fuel pump control ECU adjusts the fuel pump (for low pressure side) operation speed.

WIRING DIAGRAM

CAUTION / NOTICE / HINT

NOTICE:

Inspect the fuses for circuits related to this system before performing the following procedure.

PROCEDURE

1.	CHECK FUEL LEAK

(a) Check around and beneath the vehicle for fuel leaks, fumes, etc.

OK:

No fuel leaks present.

NG

REPAIR OR REPLACE FUEL LEAK POINT

OK

2.	PERFORM ACTIVE TEST USING TECHSTREAM (ACTIVATE THE CIRCUIT RELAY)

(a) Connect the Techstream to the DLC3.

(b) Turn the engine switch on (IG).

(c) Turn the Techstream on.

(d) Enter the following menus: Powertrain / Engine / Active Test / Activate the Circuit Relay.

Powertrain > Engine > Active Test

Tester Display
Activate the Circuit Relay

Standard:

Techstream Operation	Standard
ON	Operating sounds can be heard from fuel pump (for low pressure side)

NG

GO TO STEP 8

OK

3.	PERFORM ACTIVE TEST USING TECHSTREAM (CONTROL THE FUEL PUMP DUTY RATIO)

(a) Install the fuel pressure gauge (for low pressure line of low pressure side).

Click here

(b) Connect the Techstream to the DLC3.

(c) Turn the engine switch on (IG).

(d) Turn the Techstream on.

(e) Enter the following menus: Powertrain / Engine / Active Test / Control the Fuel Pump Duty Ratio / Data List / Fuel Pressure (Low) / Fuel Pressure 2.

Powertrain > Engine > Active Test

Active Test Display
Control the Fuel Pump Duty Ratio

Data List Display
Fuel Pressure (Low) / Fuel Pressure 2

Standard:

Techstream Operation	Standard
Low	Data List value and fuel pressure gauge are within +/-50 kPag of each other
High

HINT:

Perform "Inspection After Repair" after replacing the fuel pressure sensor (for low pressure side).

Click here

NG

REPLACE FUEL DELIVERY PIPE WITH SENSOR ASSEMBLY (FUEL PRESSURE SENSOR (FOR LOW PRESSURE SIDE))

OK

4.	READ VALUE USING TECHSTREAM (FUEL PRESSURE)

(a) Connect the Techstream to the DLC3.

(b) Turn the engine switch on (IG).

(c) Turn the Techstream on.

(d) Enter the following menus: Powertrain / Engine / Data List / Target Fuel Pressure (Low) / Target Fuel Pressure 2, Fuel Pressure (Low) / Fuel Pressure 2 and Low Fuel Pressure Sensor.

Powertrain > Engine > Data List

Tester Display
Target Fuel Pressure (Low) / Target Fuel Pressure 2
Fuel Pressure (Low) / Fuel Pressure 2
Low Fuel Pressure Sensor

Result	Proceed to
Low Fuel Pressure Sensor value is within +/- 65 kPag of the Target Fuel Pressure (Low) / Target Fuel Pressure 2	A
Low Fuel Pressure Sensor value is more than 65 kPag higher than the Target Fuel Pressure (Low) / Target Fuel Pressure 2	B
Low Fuel Pressure Sensor value is more than 65 kPag lower than the Target Fuel Pressure (Low) / Target Fuel Pressure 2	C

B

REPLACE FUEL PUMP (FOR LOW PRESSURE SIDE) Click here HINT: Relief blockage such as clogging of the jet pump is suspected.

C

GO TO STEP 7

A

5.	CHECK FUEL PRESSURE

(a) Install the fuel pressure gauge (for low pressure line of low pressure side).

Click here

(b) Start the engine.

(c) Measure the fuel pressure at idle.

Standard Fuel Pressure:

300 to 530 kPa (3.1 to 5.4 kgf/cm2, 44 to 77 psi)

HINT:

Refer to Standard Idle Speed.

Click here

(d) Stop the engine.

(e) Check that the fuel pressure remains as specified for 5 minutes.

Standard Fuel Pressure:

98 kPa (1.0 kgf/cm2, 14.2 psi) or more

HINT:

Perform "Inspection After Repair" after replacing the fuel pump (for low pressure side).

Click here

NG

REPLACE FUEL PUMP (FOR LOW PRESSURE SIDE)

OK

6.	CHECK SHORTAGE OF FUEL

(a) Connect the Techstream to the DLC3.

(b) Turn the engine switch on (IG).

(c) Turn the Techstream on.

(d) In accordance with the display on the Techstream, check the value of Freeze Frame Data item "Fuel Remaining Volume" stored when the DTC was detected.

Powertrain > Engine > DTC(P008700) > Freeze Frame Data

Tester Display
Fuel Remaining Volume

Standard:

Freeze Frame Data Item	Specified Condition
Fuel Remaining Volume	16% or more

HINT:

• DTC P008700 may be stored if the vehicle temporarily ran out of fuel when the amount of fuel was low.
• If Freeze Frame Data item "Fuel Remaining Volume" is not displayed, based on the interview with the customer, check if the low fuel level warning was not displayed when the MIL illuminated.

OK

PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE

NG

END

7.	CHECK SHORTAGE OF FUEL

(a) Check the amount of fuel remaining.

HINT:

• No fuel remains in the fuel tank: Malfunction of the fuel sender gauge assembly is suspected.
• Only the fuel pump side fuel chamber has no fuel remaining: Malfunction of the jet pump is suspected.
• Fuel remains in the fuel tank: Malfunction of the fuel pump (for low pressure side) is suspected.
• Perform "Inspection After Repair" after replacing the fuel pump (for low pressure side).

  Click here

NEXT

REPLACE FUEL PUMP (FOR LOW PRESSURE SIDE)

8.	PERFORM ACTIVE TEST USING TECHSTREAM (FUEL PUMP SINGLE PHASE ENERGIZATION)

*a	Front view of wire harness connector (to Fuel Pump (for low pressure side))

(a) Disconnect the fuel pump (for low pressure side) connector.

(b) Connect the Techstream to the DLC3.

(c) Turn the engine switch on (IG).

(d) Turn the Techstream on.

(e) Enter the following menus: Powertrain / Engine / Active Test / Fuel Pump Single Phase Energization.

Powertrain > Engine > Active Test

Tester Display
Fuel Pump Single Phase Energization

(f) Operate the fuel pump control ECU using the Active Test function and measure the voltage according to the value(s) in the table below.

Standard Voltage:

Tester Connection	GTS Operation	Specified Condition
R43-3 (BLPU) - Body ground	U Phase	4.4 to 8.4 V*
R43-4 (BLPV) - Body ground	V Phase	4.4 to 8.4 V*
R43-2 (BLPW) - Body ground	W Phase	4.4 to 8.4 V*

HINT:

• *: This Active Test restricts the fuel pump control ECU output duty cycle to 50%. Therefore, the output voltage of the fuel pump control ECU will be approximately 50% of the power source voltage.
• Before performing this inspection, check that the battery voltage is between 11 and 14 V (not depleted).
• Perform "Inspection After Repair" after replacing the fuel pump (for low pressure side).

  Click here

OK

REPLACE FUEL PUMP (FOR LOW PRESSURE SIDE)

NG

9.	CHECK HARNESS AND CONNECTOR (FUEL PUMP CONTROL ECU - FUEL PUMP (FOR LOW PRESSURE SIDE))

(a) Disconnect the fuel pump control ECU connector.

(b) Disconnect the fuel pump (for low pressure side) connector.

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

Standard Resistance:

Tester Connection	Condition	Specified Condition
R17-2 (FPU) - R43-3 (BLPU)	Always	Below 1 Ω
R17-3 (FPV) - R43-4 (BLPV)	Always	Below 1 Ω
R17-4 (FPW) - R43-2 (BLPW)	Always	Below 1 Ω
R17-2 (FPU) or R43-3 (BLPU) - Body ground and other terminals	Always	10 kΩ or higher
R17-3 (FPV) or R43-4 (BLPV) - Body ground and other terminals	Always	10 kΩ or higher
R17-4 (FPW) or R43-2 (BLPW) - Body ground and other terminals	Always	10 kΩ or higher

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR

OK

10.	CHECK HARNESS AND CONNECTOR (POWER SOURCE OF FUEL PUMP CONTROL ECU)

*a	Front view of wire harness connector (to Fuel Pump Control ECU)

(a) Disconnect the fuel pump control ECU connector.

(b) Turn the engine switch on (IG).

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

Standard Voltage:

Tester Connection	Condition	Specified Condition
R18-1 (+B) - R18-3 (GND)	Engine switch on (IG)	11 to 14 V

HINT:

Make a note of the measured voltage as it may be used in a following Active Test.

NG

GO TO STEP 13

OK

11.	INSPECT ECM (FPC TERMINAL)

*a	Front view of wire harness connector (to Fuel Pump Control ECU)

(a) Disconnect the fuel pump control ECU connector.

(b) Connect the Techstream to the DLC3.

(c) Turn the engine switch on (IG).

(d) Turn the Techstream on.

(e) Enter the following menus: Powertrain / Engine / Active Test / Fuel Pump Single Phase Energization.

Powertrain > Engine > Active Test

Tester Display
Fuel Pump Single Phase Energization

(f) Operate the fuel pump control ECU using the Active Test function and measure the resistance according to the value(s) in the table below.

Standard Resistance:

Tester Connection	Techstream Operation	Specified Condition
R18-2 (FPC) - Body ground	Before Active Test → During Active Test	Before Active Test: Resistance is stable → During Active Test: Resistance fluctuates*

HINT:

*: Using the Active Test, duty control of the transistors in the ECM will be performed. Due to the duty control, resistance of the FPC terminal will be unstable during the Active Test. If the resistance is stable before the Active Test and fluctuates while performing the Active Test, it can be determined that the transistor is operating. If the transistor does not operate during the Active Test, the ECM may be malfunctioning.

OK

REPLACE FUEL PUMP CONTROL ECU

NG

12.	CHECK HARNESS AND CONNECTOR (FUEL PUMP CONTROL ECU - ECM)

(a) Disconnect the fuel pump control ECU connector.

(b) Disconnect the ECM connector.

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

Standard Resistance:

Tester Connection	Condition	Specified Condition
R18-2 (FPC) - A21-18 (FPC)	Always	Below 1 Ω
R18-2 (FPC) or A21-18 (FPC) - Body ground and other terminals	Always	10 kΩ or higher

OK

REPLACE ECM

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR

13.	CHECK HARNESS AND CONNECTOR (FUEL PUMP CONTROL ECU - BODY GROUND)

(a) Disconnect the fuel pump control ECU connector.

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

Standard Resistance:

Tester Connection	Condition	Specified Condition
R18-3 (GND) - Body ground	Always	Below 1 Ω

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR

OK

14.	CHECK HARNESS AND CONNECTOR (POWER SOURCE VOLTAGE OF EFI-MAIN NO. 2 RELAY)

(a) Remove the EFI-MAIN NO. 2 relay from the No. 1 engine room relay block and No. 1 junction block assembly.

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

Standard Voltage:

Tester Connection	Condition	Specified Condition
3 (EFI-MAIN NO. 2 relay) - Body ground	Always	11 to 14 V

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR (BATTERY - EFI-MAIN NO. 2 RELAY)

OK

15.	INSPECT EFI-MAIN NO. 2 RELAY

(a) Inspect the EFI-MAIN NO. 2 relay.

Click here

NG

REPLACE EFI-MAIN NO. 2 RELAY

OK

16.	CHECK HARNESS AND CONNECTOR (EFI-MAIN NO. 1 RELAY - ECM)

(a) Remove the EFI-MAIN NO. 1 relay from the No. 1 engine room relay block and No. 1 junction block assembly.

(b) Disconnect the ECM connector.

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

Standard Resistance:

Tester Connection	Condition	Specified Condition
2 (EFI-MAIN NO. 1 relay) - A21-46 (MREL)	Always	Below 1 Ω
2 (EFI-MAIN NO. 1 relay) or A21-46 (MREL) - Body ground and other terminals	Always	10 kΩ or higher

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR

OK

17.	CHECK HARNESS AND CONNECTOR (EFI-MAIN NO. 1 RELAY - EFI-MAIN NO. 2 RELAY)

(a) Remove the EFI-MAIN NO. 1 and EFI-MAIN NO. 2 relays from the No. 1 engine room relay block and No. 1 junction block assembly.

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

Standard Resistance:

Tester Connection	Condition	Specified Condition
5 (EFI-MAIN NO. 1 relay) - 2 (EFI-MAIN NO. 2 relay)	Always	Below 1 Ω
5 (EFI-MAIN NO. 1 relay) or 2 (EFI-MAIN NO. 2 relay) - Body ground and other terminals	Always	10 kΩ or higher

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR

OK

18.	CHECK HARNESS AND CONNECTOR (EFI-MAIN NO. 2 RELAY - BODY GROUND)

(a) Remove the EFI-MAIN NO. 2 relay from the No. 1 engine room relay block and No. 1 junction block assembly.

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

Standard Resistance:

Tester Connection	Condition	Specified Condition
1 (EFI-MAIN NO. 2 relay) - Body ground	Always	Below 1 Ω

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR

OK

19.	CHECK HARNESS AND CONNECTOR (EFI-MAIN NO. 2 RELAY - FUEL PUMP CONTROL ECU)

(a) Remove the EFI-MAIN NO. 2 relay from the No. 1 engine room relay block and No. 1 junction block assembly.

(b) Disconnect the fuel pump control ECU connector.

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

Standard Resistance:

Tester Connection	Condition	Specified Condition
5 (EFI-MAIN NO. 2 relay) - R18-1 (+B)	Always	Below 1 Ω
5 (EFI-MAIN NO. 2 relay) or R18-1 (+B) - Body ground and other terminals	Always	10 kΩ or higher

OK

GO TO ECM POWER SOURCE CIRCUIT

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR

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