DESCRIPTION
The MIL (Malfunction Indicator Lamp) is used to indicate vehicle malfunction detections by the ECM. By turning the engine switch on (IG), 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 engine switch is first turned on (IG), the MIL should be illuminated and should then turn off. If the MIL remains illuminated or is not illuminated, conduct the following troubleshooting procedure.
If the ECM detects trouble, the MIL illuminates. At this time, the ECM records a DTC in the memory.
WIRING DIAGRAM
| *1 | from IG2 Relay |
| *2 | Combination Meter |
PROCEDURE
CHECK THAT MIL IS ILLUMINATED
Perform troubleshooting in accordance with the chart below.
| Result | ||||||
|---|---|---|---|---|---|---|
|
| B |
|
CHECK THAT MIL IS ILLUMINATED Click here |
| A |
|
CHECK IF MIL TURNS OFF
Connect the intelligent tester to the DLC3.
Turn the engine switch on (IG) and turn the tester ON.
Check if DTCs have been stored Click here. If DTCs are present, write them down.
Clear the DTCs Click here.
Check that the MIL turns off.
| OK |
|---|
| MIL turns off. |
| OK |
|
REPAIR CIRCUITS INDICATED BY OUTPUT DTCS |
| NG |
|
CHECK HARNESS AND CONNECTOR (FOR SHORT)
| *1 | ECM Connector |
Disconnect the A14 ECM connector.
Turn the engine switch on (IG).
Check that the MIL is not illuminated.
| OK |
|---|
| MIL is not illuminated. |
| OK |
|
REPLACE ECM Click here |
| NG |
|
CHECK HARNESS AND CONNECTOR (COMBINATION METER - ECM)
| *1 | Front view of wire harness connector: (to Combination Meter) |
| *2 | ECM Connector |
Disconnect the L10 combination meter connector.
Disconnect the A14 ECM connector.
Measure the resistance according to the value(s) in the table below.
| Standard resistance (check for open) | ||||||
|---|---|---|---|---|---|---|
|
| Standard resistance (check for short) | ||||||
|---|---|---|---|---|---|---|
|
| OK |
|
REPLACE NO. 1 METER ECU Click here |
| NG |
|
REPAIR OR REPLACE HARNESS OR CONNECTOR |
CHECK THAT MIL IS ILLUMINATED
Check that the MIL is illuminated when turning the engine switch on (IG).
| OK |
|---|
| MIL is illuminated. |
| OK |
|
SYSTEM OK |
| NG |
|
CHECK THAT ENGINE STARTS
Turn the engine switch on (IG).
Start the engine.
| Result | ||||||
|---|---|---|---|---|---|---|
|
Tech Tips
*: The intelligent tester cannot communicate with the ECM.
| B |
|
GO TO VC OUTPUT CIRCUIT Click here |
| A |
|
INSPECT COMBINATION METER ASSEMBLY (MIL CIRCUIT)
See the combination meter troubleshooting procedure Click here.
| OK |
|
CHECK AND REPLACE HARNESS OR CONNECTOR (COMBINATION METER - ECM) |
| NG |
|
REPLACE NO. 1 METER ECU Click here |