VC Output Circuit
1NR-FE ENGINE CONTROL: SFI SYSTEM: VC Output Circuit
- VC Output Circuit
DESCRIPTION
The ECM constantly generates 5 V power from the battery voltages supplied to the +B (BATT) terminal to operate the microprocessor. The ECM also provides this power 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 deactivated 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 when the ignition switch is turned to ON. The MIL goes off when the engine is started.
WIRING DIAGRAM
INSPECTION PROCEDURE
HINT
Refer to the Continuously Variable Transaxle System for oil pressure sensor location Locations.
PROCEDURE
1. CHECK MIL CONDITION
(a) Check that the Malfunction Indicator Lamp (MIL) lights up when turning the ignition switch to ON.
OK:
MIL lights up.
NG -- CHECK CONNECTION BETWEEN TECHSTREAM AND ECM
OK -- PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE Symptom Related Diagnostic Procedures
2. CHECK CONNECTION BETWEEN TECHSTREAM AND ECM
(a) Connect the Techstream to the DLC3.
(b) Turn the ignition switch to ON.
(c) Turn the Techstream on.
(d) Check for communication between the tester and ECM.
Result
B -- GO TO MIL CIRCUIT MIL Circuit
A -- Continue to next step.
3. CHECK MIL (THROTTLE POSITION SENSOR)
(a) Disconnect the throttle with motor body assembly connector.
(b) Turn the ignition switch to ON.
(c) Check the MIL.
Result
B -- REPLACE THROTTLE WITH MOTOR BODY ASSEMBLY Removal
A -- Continue to next step.
4. CHECK MIL (ACCELERATOR PEDAL SENSOR ASSEMBLY)
(a) Disconnect the accelerator pedal sensor assembly connector.
(b) Turn the ignition switch to ON.
(c) Check the MIL.
Result
B -- REPLACE ACCELERATOR PEDAL SENSOR ASSEMBLY Removal
A -- Continue to next step.
5. CHECK MIL (OIL PRESSURE SENSOR FOR CVT SYSTEM)
(a) Disconnect the oil pressure sensor connector.
(b) Turn the ignition switch to ON.
(c) Check the MIL.
Result
B -- REPLACE OIL PRESSURE SENSOR Removal
A -- Continue to next step.
6. CHECK MIL (CAMSHAFT POSITION SENSOR FOR INTAKE CAMSHAFT)
(a) Disconnect the camshaft position sensor (for intake camshaft) connector.
(b) Turn the ignition switch to ON.
(c) Check the MIL.
Result
B -- REPLACE CAMSHAFT POSITION SENSOR (FOR INTAKE CAMSHAFT) Removal
A -- Continue to next step.
7. CHECK MIL (CAMSHAFT POSITION SENSOR FOR EXHAUST CAMSHAFT)
(a) Disconnect the camshaft position sensor (for exhaust camshaft) connector.
(b) Turn the ignition switch to ON.
(c) Check the MIL.
Result
B -- REPLACE CAMSHAFT POSITION SENSOR (FOR EXHAUST CAMSHAFT) Removal
A -- Continue to next step.
8. CHECK MIL (CRANKSHAFT POSITION SENSOR)
(a) Disconnect the crankshaft position sensor connector.
(b) Turn the ignition switch to ON.
(c) Check the MIL.
Result
B -- REPLACE CRANKSHAFT POSITION SENSOR Removal
A -- Continue to next step.
9. CHECK MIL (CANISTER PUMP MODULE)
(a) Disconnect the canister pump module connector.
(b) Turn the ignition switch to ON.
(c) Check the MIL.
Result
B -- REPLACE CANISTER Removal
A -- Continue to next step.
10. CHECK HARNESS AND CONNECTOR (EACH SENSOR - ECM)
(a) Disconnect the throttle with motor body assembly connector.
(b) Disconnect the accelerator pedal sensor assembly connector.
(c) Disconnect the oil pressure sensor connector.
(d) Disconnect the camshaft position sensor (for intake camshaft) connector.
(e) Disconnect the camshaft position sensor (for exhaust camshaft) connector.
(f) Disconnect the crankshaft position sensor connector.
(g) Disconnect the canister pump module connector.
(h) Disconnect the ECM connectors.
(i) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- REPLACE ECM Removal