Check MIL Does Not Come ON

A: CHECK ENGINE MALFUNCTION INDICATOR LAMP (MIL) DOES NOT COME ON.

DIAGNOSIS:
- The CHECK ENGINE malfunction indicator lamp (MIL) circuit is open or shorted.

TROUBLE SYMPTOM:
- When ignition switch is turned ON (engine OFF), MIL does not come on.

Wiring Diagram:

WIRING DIAGRAM

7A1: CHECK OUTPUT SIGNAL FROM ECM.

1. Turn ignition switch to ON

Connector & Terminal - [(B134) No.11(+) - Chassis Ground(-)]:

2. Measure voltage between ECM connector and chassis ground.

CHECK: Is the voltage less than 1 V?

YES: Go to step 7A4.

NO: Go to step 7A2.

7A2: CHECK POOR CONTACT.

CHECK: Does the MIL come on when shaking or pulling ECM connector and harness?

YES: Repair poor contact in ECM connector.

NO: Go to step 7A3.

7A3: CHECK ECM CONNECTOR.

CHECK: Is ECM connector correctly connected?

YES: Replace ECM.

NO: Repair connection of ECM connector.

7A4: CHECK HARNESS BETWEEN COMBINATION METER AND ECM CONNECTOR.

1. Turn ignition switch to OFF.
2. Remove combination meter.
3. Disconnect connector from ECM and combination meter.

Connector & Terminal - [(B134) No.1 - (i12) No.12]:

4. Measure resistance of harness between ECM and combination meter connector.

CHECK: Is resistance less than 1 Ohm?

YES: Go to step 7A5.

NO: Repair harness and connector.

NOTE: In this case, repair the following:
- Open circuit in harness between ECM and combination meter connector
- Poor contact in coupling connector (B36)

7A5: CHECK POOR CONTACT.
Check poor contact in combination meter connector.

CHECK: Is there poor contact in combination meter connector?

YES: Repair poor contact in combination meter connector.

NO: Go to step 7A6.

7A6: CHECK HARNESS BETWEEN COMBINATION METER AND IGNITION SWITCH CONNECTOR.

1. Turn ignition switch to ON.

Connector & Terminal - [(i10) No.8(+) - Chassis Ground(-)]:

2. Measure voltage between combination meter connector and chassis ground.

CHECK: Is voltage more than 10 V?

YES: Go to step 7A7.

NO: Check the following and repair if necessary.

NOTE:
- Broken down ignition relay.
- Blown out fuse (No.5)
- If replaced fuse (No.5) blows easily, check the harness for short circuit of harness between fuse (No.5. and ignition relay connector.
- Open or short circuit in harness between fuse (No.5) and battery terminal
- Open circuit in harness between fuse (No.5) and ignition relay connector
- Poor contact in ignition relay connector
- Poor contact in ignition switch connector

7A7: CHECK HARNESS BETWEEN COMBINATION METER AND IGNITION SWITCH CONNECTOR.

Connector & Terminal - [(i12) No.3(+) - Chassis Ground(-)]:

Measure voltage between combination meter connector and chassis ground.

CHECK: Is voltage more than 10 V?

YES: Go to step 7A8.

NO: Check the following and repair if necessary.

NOTE:
- Broken down ignition relay.
- Blown out fuse (No.5.)
- If replaced fuse (No.5) blows easily, check the harness for short circuit of harness between fuse (No.5) and ignition relay connector.
- Open or short circuit in harness between fuse (No.5) and battery terminal
- Open circuit in harness between fuse (No.5) and ignition relay connector
- Poor contact in ignition relay connector
- Poor contact in ignition switch connector

7A8: CHECK LAMP BULB.
Remove engine malfunction indicator lamp bulb.

CHECK: Is lamp bulb condition OK?

YES: Repair combination meter connector.

NO: Replace lamp bulb.