Sfi System Vc Output Circuit
DESCRIPTION
WIRING DIAGRAM
INSPECTION PROCEDURE
CHECK MIL CONDITION
CHECK CONNECTION BETWEEN INTELLIGENT TESTER AND ECM
CHECK MIL (THROTTLE POSITION SENSOR)
CHECK MIL (ACCELERATOR PEDAL POSITION SENSOR)
CHECK HARNESS AND CONNECTOR
SFI SYSTEM - VC Output Circuit |
DESCRIPTION
The ECM constantly generates a 5 V power supply voltage from the battery voltage supplied to the +B (BATT) terminal to operate the microprocessor. The ECM also provides this power source voltage to the sensors through the VC output circuit.When the VC circuit is short-circuited, the microprocessor in the ECM and sensors that are supplied with power through the VC circuit are inactivated because the 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 for several seconds when the ignition switch is first turned to ON, and then goes off when the engine starts.
WIRING DIAGRAM
INSPECTION PROCEDURE
Check that the Malfunction Indicator Lamp (MIL) lights up when turning the ignition switch to ON.
- OK:
- MIL lights up.
2.CHECK CONNECTION BETWEEN INTELLIGENT TESTER AND ECM |
Connect the intelligent tester to the DLC3.
Turn the ignition switch to ON.
Turn the tester on.
Check the communication between the tester and ECM.
ResultResult
| Proceed to
|
Communication is possible
| A
|
Communication is not possible
| B
|
3.CHECK MIL (THROTTLE POSITION SENSOR) |
Disconnect the throttle body with motor assembly connector.
Turn the ignition switch to ON.
Check the MIL.
ResultResult
| Proceed to
|
MIL illuminates
| A
|
MIL does not illuminate
| B
|
Reconnect the throttle body with motor assembly connector.
4.CHECK MIL (ACCELERATOR PEDAL POSITION SENSOR) |
Disconnect the accelerator pedal rod assembly connector.
Turn the ignition switch to ON.
Check the MIL.
ResultResult
| Proceed to
|
MIL illuminates
| A
|
MIL does not illuminate
| B
|
Reconnect the accelerator pedal rod assembly connector.
5.CHECK HARNESS AND CONNECTOR |
Disconnect the throttle body with motor assembly connector.
Disconnect the accelerator pedal rod 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
|
C95-10 (VCTA) - Body ground
| Always
| 10 kΩ or higher
|
G146-4 (VCPA) - Body ground
| Always
| 10 kΩ or higher
|
G146-3 (VCP2) - Body ground
| Always
| 10 kΩ or higher
|
Reconnect the throttle body with motor assembly connector.
Reconnect the accelerator pedal rod assembly connector.
Reconnect the ECM connectors.
| REPAIR OR REPLACE HARNESS OR CONNECTOR |
|
|