DESCRIPTION
The MIL (Malfunction Indicator Lamp) is used to indicate vehicle malfunctions detected by the ECM.
When the ignition switch is turned to ON, power is supplied to the MIL circuit, and the ECM provides the circuit ground, which illuminates the MIL.
The MIL operation can be checked visually. When the ignition switch is first turned to ON, the MIL should be illuminated and should then turn off when the engine is started. If the MIL remains illuminated or is not illuminated, conduct the following troubleshooting procedure using the intelligent tester.
WIRING DIAGRAM
CAUTION / NOTICE / HINT
Note
Inspect the fuses for circuits related to this system before performing the following inspection procedure.
Perform electronic throttle learning after replacing the ECM Click here.
PROCEDURE
CHECK THAT MIL IS ILLUMINATED
Perform troubleshooting in accordance with the table below.
| Result | Proceed to |
|---|---|
| MIL remains on | A |
| MIL does not illuminate | B |
| B |
|
CHECK THAT MIL IS ILLUMINATED Click here |
| A |
|
CHECK WHETHER MIL TURNS OFF
Connect the intelligent tester to the DLC3.
Turn the ignition switch to ON.
Turn the tester on.
Enter the following menus: Powertrain / Engine and ECT / DTC.
Check if any DTCs have been detected. Note down any DTCs.
| Result | Proceed to |
|---|---|
| NO DTC detected | A |
| Any DTCs detected | B |
Tech Tips
Check for detected DTCs output from other ECUs which relate to the MIL.
| B |
|
REPAIR CIRCUITS INDICATED BY OUTPUT DTCS Click here |
| A |
|
CHECK HARNESS AND CONNECTOR (CHECK FOR SHORT IN WIRE HARNESS)
Disconnect the ECM connector.
Turn the ignition switch to ON.
Check that the MIL is not illuminated.
| OK |
|---|
| MIL is not illuminated. |
| OK |
|
REPLACE ECM Click here |
| NG |
|
CHECK HARNESS AND CONNECTOR (COMBINATION METER ASSEMBLY - ECM)
Disconnect the combination meter assembly connector.
Disconnect the ECM connector.
Measure the resistance according to the value(s) in the table below.
| Standard Resistance | ||||||
|---|---|---|---|---|---|---|
|
| OK |
|
REPLACE COMBINATION METER ASSEMBLY Click here |
| NG |
|
REPAIR OR REPLACE HARNESS OR CONNECTOR |
CHECK THAT MIL IS ILLUMINATED
Check if the MIL is illuminates when the ignition switch is turned to ON.
| OK |
|---|
| MIL is illuminated. |
| OK |
|
CHECK FOR INTERMITTENT PROBLEMS Click here |
| NG |
|
CHECK THAT ENGINE STARTS
Turn the ignition switch to ON.
Start the engine.
| Result | Proceed to |
|---|---|
| Engine starts | A |
| Engine does not start* | B |
Tech Tips
*: The intelligent tester cannot communicate with the ECM.
| B |
|
GO TO VC OUTPUT CIRCUIT Click here |
| A |
|
CHECK HARNESS AND CONNECTOR (COMBINATION METER ASSEMBLY - ECM)
Disconnect the combination meter assembly connector.
Disconnect the ECM connector.
Measure the resistance according to the value(s) in the table below.
| Standard Resistance | ||||||
|---|---|---|---|---|---|---|
|
| OK |
|
REPLACE COMBINATION METER ASSEMBLY Click here |
| NG |
|
REPAIR OR REPLACE HARNESS OR CONNECTOR |