DESCRIPTION
The ECM constantly generates 5 V of 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.
Tech Tips
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.
WIRING DIAGRAM
INSPECTION PROCEDURE
Note
Inspect the fuses of circuits related to this system before performing the following inspection procedure.
After replacing the ECM, the new ECM needs registration Click here and initialization Click here.
After replacing the fuel supply pump assembly, the ECM needs initialization Click here.
After replacing an injector assembly, the ECM needs registration Click here.
PROCEDURE
CHECK MIL
Check that the Malfunction Indicator Lamp (MIL) lights up when turning the engine switch on (IG).
| Result | Proceed to |
|---|---|
| MIL illuminates | A |
| MIL does not illuminate | B |
| A |
|
END |
| B |
|
CHECK COMMUNICATION BETWEEN INTELLIGENT TESTER AND ECM
Connect the intelligent tester 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 |
| A |
|
GO TO MIL CIRCUIT Click here |
| B |
|
CHECK MIL (ACCELERATOR PEDAL POSITION SENSOR)
Disconnect the 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 |
Reconnect the accelerator pedal position sensor connector.
| A |
|
REPLACE ACCELERATOR PEDAL ROD ASSEMBLY Click here |
| B |
|
CHECK MIL (THROTTLE POSITION SENSOR)
Disconnect the throttle position sensor connector.
Turn the engine switch on (IG).
Check the MIL.
| Result | Proceed to |
|---|---|
| MIL illuminates | A |
| MIL does not illuminate | B |
Reconnect the throttle position sensor connector.
| A |
|
REPLACE DIESEL THROTTLE BODY ASSEMBLY Click here |
| B |
|
CHECK MIL (FUEL PRESSURE SENSOR)
Disconnect the fuel pressure sensor connector.
Turn the engine switch on (IG).
Check the MIL.
| Result | Proceed to |
|---|---|
| MIL illuminates | A |
| MIL does not illuminate | B |
Reconnect the fuel pressure sensor connector.
| A |
|
REPLACE COMMON RAIL ASSEMBLY Click here |
| B |
|
CHECK MIL (ELECTRIC EGR CONTROL VALVE ASSEMBLY)
Disconnect the electric EGR control valve assembly connector.
Turn the engine switch on (IG).
Check the MIL.
| Result | Proceed to |
|---|---|
| MIL illuminates | A |
| MIL does not illuminate | B |
Reconnect the electric EGR control valve assembly connector.
| A |
|
REPLACE ELECTRIC EGR CONTROL VALVE ASSEMBLY Click here |
| B |
|
CHECK MIL (OIL PRESSURE SENDER GAUGE ASSEMBLY)
Disconnect the oil pressure sender gauge assembly connector.
Turn the engine switch on (IG).
Check the MIL.
| Result | Proceed to |
|---|---|
| MIL illuminates | A |
| MIL does not illuminate | B |
Reconnect the oil pressure sender gauge assembly connector.
| A |
|
REPLACE OIL PRESSURE SENDER GAUGE ASSEMBLY Click here |
| B |
|
CHECK MIL (DIFFERENTIAL PRESSURE SENSOR ASSEMBLY)
Disconnect the differential pressure sensor assembly connector.
Turn the engine switch on (IG).
Check the MIL.
| Result | Proceed to |
|---|---|
| MIL illuminates | A |
| MIL does not illuminate | B |
Reconnect the differential pressure sensor assembly connector.
| A |
|
REPLACE DIFFERENTIAL PRESSURE SENSOR ASSEMBLY Click here |
| B |
|
CHECK MIL (MANIFOLD ABSOLUTE PRESSURE SENSOR)
Disconnect the manifold absolute pressure sensor connector.
Turn the engine switch on (IG).
Check the MIL.
| Result | Proceed to |
|---|---|
| MIL illuminates | A |
| MIL does not illuminate | B |
Reconnect the manifold absolute pressure sensor connector.
| A |
|
REPLACE MANIFOLD ABSOLUTE PRESSURE SENSOR |
| B |
|
CHECK MIL (NOZZLE VANE POSITION SENSOR)
Disconnect the nozzle vane position sensor connector.
Turn the engine switch on (IG).
Check the MIL.
| Result | Proceed to |
|---|---|
| MIL illuminates | A |
| MIL does not illuminate | B |
Reconnect the nozzle vane position sensor connector.
| A |
|
REPLACE TURBOCHARGER SUB-ASSEMBLY Click here |
| B |
|
CHECK HARNESS AND CONNECTOR
Disconnect the accelerator pedal position sensor connector.
Disconnect the throttle position sensor connector.
Disconnect the fuel pressure sensor connector.
Disconnect the electric EGR control valve assembly connector.
Disconnect the oil pressure sender gauge assembly connector.
Disconnect the differential pressure sensor assembly connector.
Disconnect the nozzle vane position sensor connector.
Disconnect the manifold absolute pressure sensor connector.
Disconnect the ECM connectors.
Measure the resistance according to the value(s) in the table below.
| Standard Resistance | |||||||||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
|
Reconnect the accelerator pedal position sensor connector.
Reconnect the throttle position sensor connector.
Reconnect the fuel pressure sensor connector.
Reconnect the electric EGR control valve assembly connector.
Reconnect the oil pressure sender gauge assembly connector.
Reconnect the differential pressure sensor assembly connector.
Reconnect the nozzle vane position sensor connector.
Reconnect the manifold absolute pressure sensor connector.
Reconnect the ECM connectors.
| NG |
|
REPAIR OR REPLACE HARNESS OR CONNECTOR |
| OK |
|
REPLACE ECM Click here