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 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.
Under normal conditions, the MIL is illuminated for several seconds when the engine switch is first turned on (IG). The MIL goes off when the engine is started.
INSPECTION PROCEDURE
PROCEDURE
CHECK MIL
Check that the Malfunction Indicator Lamp (MIL) lights up when turning the engine switch on (IG).
| OK |
|---|
| MIL lights up |
CHECK COMMUNICATION BETWEEN GTS AND ECM
Connect the GTS to the DLC3.
Turn the engine switch on (IG) and tester on.
Check the communication between the tester and ECM.
| Result | Proceed to |
|---|---|
| Communication is possible | A |
| Communication is not possible | B |
CHECK MIL (THROTTLE POSITION SENSOR)
Disconnect the C3 throttle body connector.
Turn the engine switch on (IG).
Check the MIL.
| Result | Proceed to |
|---|---|
| MIL illuminates | A |
| MIL does not illuminate | B |
CHECK MIL (ACCELERATOR PEDAL POSITION SENSOR)
Disconnect the A31 accelerator pedal position sensor connector.
Turn the engine switch on (IG).
Check the MIL.
| Result | Proceed to |
|---|---|
| MIL illuminates | A |
| MIL does not illuminate | B |
CHECK MIL (POWER STEERING OIL PRESSURE SENSOR)
Disconnect the C59 power steering oil pressure sensor connector.
Turn the engine switch on (IG).
Check the MIL.
| Result | Proceed to |
|---|---|
| MIL illuminates | A |
| MIL does not illuminate | B |
CHECK MIL (CAMSHAFT POSITION SENSOR)
Disconnect the C99 camshaft position sensor connector.
Turn the engine switch on (IG).
Check the MIL.
| Result | Proceed to |
|---|---|
| MIL illuminates | A |
| MIL does not illuminate | B |
CHECK MIL (CRANKSHAFT POSITION SENSOR)
Disconnect the C114 crankshaft position sensor connector.
Turn the engine switch on (IG).
Check the MIL.
| Result | Proceed to |
|---|---|
| MIL illuminates | A |
| MIL does not illuminate | B |
CHECK MIL (VVT SENSOR for Intake Side of Bank 1)
Disconnect the C100 VVT sensor (for Intake Side of Bank 1) connector.
Turn the engine switch on (IG).
Check the MIL.
| Result | Proceed to |
|---|---|
| MIL illuminates | A |
| MIL does not illuminate | B |
CHECK MIL (VVT SENSOR for Exhaust Side of Bank 1)
Disconnect the C121T sensor (for Exhaust Side of Bank 1) connector.
Turn the engine switch on (IG).
Check the MIL.
| Result | Proceed to |
|---|---|
| MIL illuminates | A |
| MIL does not illuminate | B |
CHECK MIL (VVT SENSOR for Intake Side of Bank 2)
Disconnect the C101 VVT sensor (for Intake Side of Bank 2) connector.
Turn the engine switch on (IG).
Check the MIL.
| Result | Proceed to |
|---|---|
| MIL illuminates | A |
| MIL does not illuminate | B |
CHECK MIL (VVT SENSOR for Exhaust Side of Bank 2)
Disconnect the C122T sensor (for Exhaust Side of Bank 2) connector.
Turn the engine switch on (IG).
Check the MIL.
| Result | Proceed to |
|---|---|
| MIL illuminates | A |
| MIL does not illuminate | B |
CHECK HARNESS AND CONNECTOR
Disconnect the C3 throttle body connector.
Disconnect the A31 accelerator pedal position sensor connector.
Disconnect the C59 power steering oil pressure sensor connector.
Disconnect the C99 camshaft position sensor connector.
Disconnect the C114 crankshaft position sensor connector.
Disconnect the C100 VVT sensor (for Intake Side of Bank 1) connector.
Disconnect the C121 VVT sensor (for Exhaust Side of Bank 1) connector.
Disconnect the C101 VVT sensor (for Intake Side of Bank 2) connector.
Disconnect the C122 VVT sensor (for Exhaust Side of Bank 2) connector.
Disconnect the ECM connectors.
Measure the resistance according to the value(s) in the table below.
| Standard Resistance | ||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
|
GO TO MIL CIRCUITClick here
REPLACE THROTTLE BODY ASSEMBLYClick here
REPLACE ACCELERATOR PEDAL POSITION SENSORClick here
REPLACE POWER STEERING OIL PRESSURE SENSORClick here
REPLACE CAMSHAFT POSITION SENSORClick here
REPLACE CRANKSHAFT POSITION SENSORClick here
REPLACE VVT SENSOR (for Intake Side of Bank 1)Click here
REPLACE VVT SENSOR (for Exhaust Side of Bank 1)Click here
REPLACE VVT SENSOR (for Intake Side of Bank 2)Click here
REPLACE VVT SENSOR (for Exhaust Side of Bank 2)Click here
REPAIR OR REPLACE HARNESS OR CONNECTOR
SYSTEM OK
REPLACE ECMClick here