2NZ-FE ENGINE CONTROL SFI SYSTEM VC Output Circuit

DESCRIPTION

The ECM constantly generates a 5 V power source voltage from the battery voltage supplied to the +B, +B2 (BATT) terminal to operate the microprocessor. The ECM also provides this power source voltage to the sensors through the VC output circuit.

4.375,1.177 6.198,1.354 1.823,0.177 10 false 5 V Constant Voltage Circuit 5.354,2.031 6.365,2.188 1.01,0.156 10 false Microprocessor 1.083,1.125 2.823,1.365 1.74,0.24 10 false from ECU-B NO. 3 Fuse 1.281,1.479 2.646,1.646 1.365,0.167 10 false from EFI NO. 1 Fuse 2.906,1 3.427,1.219 0.521,0.219 10 false BATT 0.313,2.135 2.635,2.677 2.323,0.542 10 false Throttle Position Sensor, Accelerator Pedal Position Sensor, etc. (Sensors which have IC) 0.313,3.021 2.677,3.448 2.365,0.427 10 false Engine Coolant Temperature Sensor, Intake Air Temperature Sensor, etc. 4.073,3.115 4.333,3.323 0.26,0.208 10 false R 2.813,1.354 3.375,1.552 0.563,0.198 10 false +B, +B2 3.167,2.271 3.458,2.5 0.292,0.229 10 false VC 4.885,3.333 5.229,3.51 0.344,0.177 10 false ECM

When the VC circuit is short-circuited, the microprocessor in the ECM and the sensors that are supplied with power through the VC circuit are inactivated because power is not supplied from the VC circuit. Under this condition, the system does not start up and the MIL does not illuminate even if the system malfunctions.

HINT:: Under normal conditions, the MIL is illuminated when the ignition switch is turned to ON. The MIL goes off when the engine is started.

WIRING DIAGRAM

5,0.479 5.438,0.646 0.438,0.167 10 false VCTA 4.667,0.583 4.969,0.792 0.302,0.208 10 false B56 4.729,0.406 4.958,0.615 0.229,0.208 10 false 67 2.5,0.469 2.729,0.656 0.229,0.188 10 false 5 5,1.021 5.438,1.229 0.438,0.208 10 false VTA1 4.667,1.031 4.948,1.24 0.281,0.208 10 false B56 4.677,0.854 4.938,1.063 0.26,0.208 10 false 115 5,1.458 5.438,1.667 0.438,0.208 10 false VTA2 4.667,1.49 4.958,1.698 0.292,0.208 10 false B56 4.677,1.313 4.938,1.521 0.26,0.208 10 false 114 5,1.844 5.438,2.01 0.438,0.167 10 false ETA 4.667,1.948 4.948,2.156 0.281,0.208 10 false B56 4.719,1.771 4.948,1.979 0.229,0.208 10 false 91 4.99,3.26 5.427,3.427 0.438,0.167 10 false VCPA 4.656,3.354 4.958,3.563 0.302,0.208 10 false A56 4.729,3.177 4.958,3.385 0.229,0.208 10 false 57 2.531,3.24 2.76,3.427 0.229,0.188 10 false 4 4.99,3.719 5.427,3.885 0.438,0.167 10 false VCP2 4.656,3.813 4.948,4.021 0.292,0.208 10 false A56 4.719,3.635 4.948,3.844 0.229,0.208 10 false 58 2.531,3.688 2.76,3.875 0.229,0.188 10 false 1 4.99,4.26 5.427,4.469 0.438,0.208 10 false VPA 4.656,4.271 4.927,4.479 0.271,0.208 10 false A56 4.719,4.083 4.948,4.292 0.229,0.208 10 false 55 2.531,4.146 2.76,4.333 0.229,0.188 10 false 6 4.99,4.708 5.427,4.917 0.438,0.208 10 false VPA2 4.656,4.719 4.938,4.927 0.281,0.208 10 false A56 4.719,4.552 4.948,4.76 0.229,0.208 10 false 56 2.531,4.604 2.76,4.792 0.229,0.188 10 false 3 4.99,5.083 5.427,5.25 0.438,0.167 10 false EPA 4.656,5.177 4.927,5.385 0.271,0.208 10 false A56 4.719,5 4.948,5.208 0.229,0.208 10 false 59 2.531,5.063 2.76,5.25 0.229,0.188 10 false 5 4.99,5.542 5.427,5.708 0.438,0.167 10 false EPA2 2.146,0.563 2.417,0.771 0.271,0.208 10 false VC 2.083,1.01 2.396,1.219 0.313,0.208 10 false VTA 2,1.469 2.438,1.677 0.438,0.208 10 false VTA2 2.156,1.917 2.417,2.125 0.26,0.208 10 false E2 1.99,3.344 2.427,3.552 0.438,0.208 10 false VCPA 1.99,3.802 2.427,4.01 0.438,0.208 10 false VCP2 2.083,4.24 2.417,4.448 0.333,0.208 10 false VPA 1.99,4.698 2.427,4.906 0.438,0.208 10 false VPA2 2.083,5.156 2.417,5.365 0.333,0.208 10 false EPA 1.99,5.625 2.427,5.833 0.438,0.208 10 false EPA2 4.656,5.635 4.948,5.844 0.292,0.208 10 false A56 4.729,5.469 4.958,5.677 0.229,0.208 10 false 60 2.531,5.521 2.76,5.708 0.229,0.188 10 false 2 5.552,6.469 5.99,6.625 0.438,0.156 10 false ECM 2.5,0.927 2.729,1.115 0.229,0.188 10 false 6 2.5,1.375 2.729,1.563 0.229,0.188 10 false 4 2.5,1.844 2.729,2.031 0.229,0.188 10 false 3 0.094,2.438 4.76,2.76 4.667,0.323 10 false B60 Throttle Position Sensor (Throttle Body with Motor Assembly) 0.094,6.146 4.906,6.625 4.813,0.479 10 false A2 Accelerator Pedal Position Sensor (Accelerator Pedal Sensor Assembly)

PROCEDURE

1.CHECK MIL CONDITION

Check that the Malfunction Indicator Lamp (MIL) lights up when the ignition switch is turned to ON.

OK:: MIL lights up.

Result:

Proceed to
OK
NG

PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE

Click hereEngine / Hybrid System>2NZ-FE ENGINE CONTROL>SFI SYSTEM>PROBLEM SYMPTOMS TABLE

2.CHECK CONNECTION BETWEEN GTS AND ECM

Connect the GTS to the DLC3.

Turn the ignition switch to ON.

Turn the GTS on.

Check for communication between the GTS and ECM.

Result:

Result	Proceed to
Communication is not possible	A
Communication is possible	B

3.CHECK MIL (THROTTLE POSITION SENSOR)

GO TO MIL CIRCUIT

Click hereEngine / Hybrid System>2NZ-FE ENGINE CONTROL>SFI SYSTEM>MIL Circuit

3.CHECK MIL (THROTTLE POSITION SENSOR)

Disconnect the throttle body with motor assembly connector.

Turn the ignition switch to ON.

Check the MIL.

Result:

Result	Proceed to
MIL does not illuminate	A
MIL illuminates	B

4.CHECK MIL (ACCELERATOR PEDAL SENSOR ASSEMBLY)

REPLACE THROTTLE BODY WITH MOTOR ASSEMBLY

Click hereEngine / Hybrid System>2NZ-FE ENGINE CONTROL>THROTTLE BODY>REMOVAL

4.CHECK MIL (ACCELERATOR PEDAL SENSOR ASSEMBLY)

Disconnect the accelerator pedal sensor assembly connector.

Turn the ignition switch to ON.

Check the MIL.

Result:

Result	Proceed to
MIL does not illuminate	A
MIL illuminates	B

5.CHECK HARNESS AND CONNECTOR

REPLACE ACCELERATOR PEDAL SENSOR ASSEMBLY

Click hereEngine / Hybrid System>2NZ-FE ENGINE CONTROL>ACCELERATOR PEDAL>REMOVAL

5.CHECK HARNESS AND CONNECTOR

Disconnect the throttle body with motor assembly connector.

Disconnect the accelerator pedal sensor assembly connector.

Disconnect the ECM connectors.

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

Standard Resistance:

Tester Connection	Condition	Specified Condition
B56-67 (VCTA) - Body ground	Always	10 kΩ or higher
A56-57 (VCPA) - Body ground	Always	10 kΩ or higher
A56-58 (VCP2) - Body ground	Always	10 kΩ or higher

Result:

Proceed to
OK
NG

REPLACE ECM

Click hereEngine / Hybrid System>2NZ-FE ENGINE CONTROL>ECM>REMOVAL

REPAIR OR REPLACE HARNESS OR CONNECTOR