| Last Modified: 11-29-2007 | 1.6 J | |
| Service Category: Engine/Hybrid System | Section: Engine Control | |
| Model Year: 2008 | Model: Sequoia | Doc ID: RM0000030MH00KX |
| Title: 2UZ-FE ENGINE CONTROL: SFI SYSTEM: DESCRIPTION (2008 Sequoia) | ||
|
Fuel Pump Control Circuit |
DESCRIPTION
The fuel pump circuit consists of the ECM, fuel pump and fuel pump ECU (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 ECU. Based on the signal sent from the ECM, the fuel pump ECU adjusts the fuel pump operation speed between 3 settings.
WIRING DIAGRAM
INSPECTION PROCEDURE
This troubleshooting procedure is based on the premise that the engine is started. If the engine is not started, proceed to the Problem Symptoms Table
.
PROCEDURE
|
1. |
PERFORM ACTIVE TEST USING TECHSTREAM (FUEL PUMP) |
(a) Connect the Techstream to the DLC3.
(b) Turn the ignition switch to ON.
(c) Turn the Techstream ON.
(d) Enter the following menus: Powertrain / Engine / Active Test / Control the Fuel Pump / Speed.
(e) Check whether operating sounds can be heard while operating the relay using the Techstream.
OK:
Operating sounds can be heard from relay.
|
|
2. |
CHECK HARNESS AND CONNECTOR (FUEL PUMP ECU - ECM AND BODY GROUND) |
(a) Disconnect the fuel pump 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 |
|---|---|---|
|
O35-1 (FPC) - A27-52 (FPC) |
Always |
Below 1 Ω |
|
O35-2 (DI) - A27-18 (DI) |
Always |
Below 1 Ω |
|
O35-3 (E) - Body ground |
Always |
Below 1 Ω |
|
O35-1 (FPC) or A27-52 (FPC) - Body ground |
Always |
10 kΩ or higher |
|
O35-2 (DI) or A27-18 (DI) - Body ground |
Always |
10 kΩ or higher |
|
|
3. |
INSPECT FUEL PUMP ECU (FPC SIGNAL) |
(a) Disconnect the fuel pump ECU connector.
(b) Crank the engine.
(c) Measure the voltage according to the value(s) in the table below.
Standard Voltage:
|
Tester Connection |
Condition |
Specified Condition |
|---|---|---|
|
O35-1 (FPC) - O35-3 (E) |
Engine cranking |
2.8 V or higher |
|
|
5. |
INSPECT CIRCUIT OPENING RELAY (C/OPN) |
(a) Remove the circuit opening relay (C/OPN) from the engine room relay block.
(b) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
|
Tester Connection |
Condition |
Specified Condition |
|---|---|---|
|
3 - 5 |
When battery voltage not applied |
10 kΩ or higher |
|
3 - 5 |
When battery voltage applied to terminals 1 and 2 |
Below 1 Ω |
|
|
6. |
INSPECT CIRCUIT OPENING RELAY (POWER SOURCE VOLTAGE) |
(a) Remove the circuit opening relay (C/OPN) from the engine room relay block.
(b) Turn the ignition switch to ON.
(c) Measure the voltage according to the value(s) in the table below.
Standard Voltage:
|
Tester Connection |
Switch Condition |
Specified Condition |
|---|---|---|
|
C/OPN relay (2) - Body ground |
Ignition switch ON |
11 to 14 V |
|
C/OPN relay (5) - Body ground |
Ignition switch ON |
11 to 14 V |
|
|
7. |
CHECK HARNESS AND CONNECTOR (CIRCUIT OPENING RELAY (C/OPN) - ECM AND FUEL PUMP ECU) |
(a) Remove the circuit opening relay (C/OPN) from the engine room relay block.
(b) Disconnect the ECM connector.
(c) Disconnect the fuel pump ECU connector.
(d) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
|
Tester Connection |
Condition |
Specified Condition |
|---|---|---|
|
C/OPN relay (1) - A27-48 (FC) |
Always |
Below 1 Ω |
|
C/OPN relay (3) - O35-4 (+B) |
Always |
Below 1 Ω |
|
C/OPN relay (1) or A27-48 (FC) - Body ground |
Always |
10 kΩ or higher |
|
C/OPN relay (3) or O35-4 (+B) - Body ground |
Always |
10 kΩ or higher |
|
|
8. |
CHECK HARNESS AND CONNECTOR (FUEL PUMP - FUEL PUMP ECU) |
(a) Disconnect the fuel pump connector.
(b) Disconnect the fuel pump ECU connector.
(c) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
|
Tester Connection |
Condition |
Specified Condition |
|---|---|---|
|
Q1-4 (B2) - O36-1 (FP) |
Always |
Below 1 Ω |
|
Q1-5 (E2) - O36-2 (FP-) |
Always |
Below 1 Ω |
|
Q1-4 (B2) or O36-1 (FP) - Body ground |
Always |
10 kΩ or higher |
|
Q1-5 (E2) or O36-2 (FP-) - Body ground |
Always |
10 kΩ or higher |
|
|
9. |
INSPECT FUEL PUMP |
(a) Inspect the fuel pump
.
|
|
10. |
CHECK HARNESS AND CONNECTOR (FUEL PUMP ECU - ECM AND BODY GROUND) |
(a) Disconnect the fuel pump 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 |
|---|---|---|
|
O35-1 (FPC) - A27-52 (FPC) |
Always |
Below 1 Ω |
|
O35-2 (DI) - A27-18 (DI) |
Always |
Below 1 Ω |
|
O35-3 (E) - Body ground |
Always |
Below 1 Ω |
|
O35-1 (FPC) or A27-52 (FPC) - Body ground |
Always |
10 kΩ or higher |
|
O35-2 (DI) or A27-18 (DI) - Body ground |
Always |
10 kΩ or higher |
|
|
11. |
INSPECT FUEL PUMP ECU (FPC SIGNAL) |
(a) Disconnect the fuel pump ECU connector.
(b) Crank the engine.
(c) Measure the voltage according to the value(s) in the table below.
Standard Voltage:
|
Tester Connection |
Condition |
Specified Condition |
|---|---|---|
|
O35-1 (FPC) - O35-3 (E) |
Engine cranking |
2.8 V or higher |
|
|
13. |
CHECK HARNESS AND CONNECTOR (CIRCUIT OPENING RELAY (C/OPN) - IGN FUSE AND INTEGRATION RELAY) |
(a) Remove the circuit opening relay (C/OPN) from the engine room relay block.
(b) Remove the IGN fuse from the engine room relay block.
(c) Remove the integration relay from the engine room relay block.
(d) Disconnect the 1B integration relay connector.
(e) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
|
Tester Connection |
Condition |
Specified Condition |
|---|---|---|
|
C/OPN relay (2) - IGN fuse (2) |
Always |
Below 1 Ω |
|
C/OPN relay (5) - 1B-4 |
Always |
Below 1 Ω |
|
C/OPN relay (2) or IGN fuse (2) - Body ground |
Always |
10 kΩ or higher |
|
C/OPN relay (5) or 1B-4 - Body ground |
Always |
10 kΩ or higher |
|
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