CHECK COMMUNICATION BETWEEN TECHSTREAM AND ECM
CHECK MIL (THROTTLE POSITION SENSOR)
CHECK MIL (ACCELERATOR PEDAL POSITION SENSOR)
CHECK MIL (CANISTER PUMP MODULE)
CHECK MIL (CAMSHAFT POSITION SENSOR FOR INTAKE CAMSHAFT)
CHECK MIL (CAMSHAFT POSITION SENSOR FOR EXHAUST CAMSHAFT)
CHECK HARNESS AND CONNECTOR (VC CIRCUIT)
SFI SYSTEM - VC Output Circuit |
DESCRIPTION
The ECM constantly generates 5 V power from the battery voltage 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 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 when the ignition switch is turned ON. The MIL goes off when the engine is started.
WIRING DIAGRAM

INSPECTION PROCEDURE
1.CHECK MIL |
Check that the Malfunction Indicator Lamp (MIL) lights up when turning the ignition switch to ON.
- OK:
- MIL lights up
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OK | ||
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2.CHECK COMMUNICATION BETWEEN TECHSTREAM AND ECM |
Connect the Techstream to the DLC3.
Turn the ignition switch to ON.
Turn the Techstream on.
Check the communication between the Techstream and ECM.
- Result:
Result Proceed to Communication is possible A Communication is not possible B
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B | |
3.CHECK MIL (THROTTLE POSITION SENSOR) |
Disconnect the throttle body connector.
Turn the ignition switch to ON.
Check the MIL.
- Result:
Result Proceed to MIL illuminates A MIL does not illuminate B
Reconnect the throttle body connector.
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B | |
4.CHECK MIL (ACCELERATOR PEDAL POSITION SENSOR) |
Disconnect the accelerator pedal position sensor connector.
Turn the ignition switch to ON.
Check the MIL.
- Result:
Result Proceed to MIL illuminates A MIL does not illuminate B
Reconnect the accelerator pedal position sensor connector.
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B | |
5.CHECK MIL (CANISTER PUMP MODULE) |
Disconnect the canister pump module connector.
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Turn the ignition switch to ON.
Check the MIL.
- Result:
Result Proceed to MIL illuminates A MIL does not illuminate B
Reconnect the canister pump module connector.
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B | |
6.CHECK MIL (CAMSHAFT POSITION SENSOR FOR INTAKE CAMSHAFT) |
Disconnect the camshaft position sensor (for intake camshaft) connector.
Turn the ignition switch to ON.
Check the MIL.
- Result:
Result Proceed to MIL illuminates A MIL does not illuminate B
Reconnect the camshaft position sensor (for intake camshaft).
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B | |
7.CHECK MIL (CAMSHAFT POSITION SENSOR FOR EXHAUST CAMSHAFT) |
Disconnect the camshaft position sensor (for exhaust camshaft) connector.
Turn the ignition switch to ON.
Check the MIL.
- Result:
Result Proceed to MIL illuminates A MIL does not illuminate B
Reconnect the camshaft position sensor (for exhaust camshaft).
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B | |
8.CHECK HARNESS AND CONNECTOR (VC CIRCUIT) |
Disconnect the throttle body connector.
Disconnect the accelerator pedal position sensor connector.
Disconnect the canister pump module connector.
Disconnect the camshaft position sensor (for intake camshaft) connector.
Disconnect the camshaft position sensor (for exhaust camshaft) connector.
Disconnect the ECM connectors.
Measure the resistance.
- Standard Resistance (Check for Short):
Tester Connection Condition Specified Condition B31-89 (VCTA) - Body ground Always 10 kΩ or higher A50-57 (VCPA) - Body ground Always 10 kΩ or higher A50-58 (VCP2) - Body ground Always 10 kΩ or higher B31-116 (VCPP) - Body ground Always 10 kΩ or higher B31-119 (VCV1) - Body ground Always 10 kΩ or higher B31-121 (VCE1) - Body ground Always 10 kΩ or higher
Reconnect the throttle body connector.
Reconnect the accelerator pedal position sensor connector.
Reconnect the canister pump module connector.
Reconnect the camshaft position sensor (for intake camshaft) connector.
Reconnect the camshaft position sensor (for exhaust camshaft) connector.
Reconnect the ECM connectors.
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OK | ||
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