Inspection Procedure 3: The Engine Warning Lamp Does Not Illuminate Right after the Ignition Switch is Turned the "ON" Position

OPERATION

Battery voltage is applied to engine warning lamp of combination meter connector (terminal No. 42) from ignition switch.

Engine-A/T-ECU (terminal No. 7) makes power transistor in unit be in "ON" position, and that makes currents go on engine warning lamp of combination meter connector (terminal No. 14).

COMMENTS ON TROUBLE SYMPTOM

Engine-A/T-ECU turns on engine warning lamp for 5 seconds to check for burnt-out bulb immediately after ignition switch is turned to ON.

If engine warning lamp is not lit just after turning ignition switch to "ON" position, failure is possibly caused by burn-out bulb, open/short circuit or other faults.

PROBABLE CAUSE

Engine warming lamp bulb burnt out

Failed ignition switch

Open/short circuit in engine warning lamp circuit for or loose connector contact

Failed engine-A/T-ECU

DIAGNOSIS PROCEDURE

STEP 1: Check engine start-up.

Q: Is engine started?

YES: Go to Step 2

.
NO: Check engine-A/T-ECU power supply, engine control relay and ignition switch IG1 system (Refer to Inspection Procedure 24

STEP 2: Check engine warning lamp for burnt-out bulb.

Q: Is the check result normal?

YES: Go to Step 3

.
NO: Replace engine warning lamp.

STEP 3: Connector check: C-04 combination meter connector

Q: Is the check result normal?

YES: Go to Step 4

.
NO: Repair.

STEP 4: Perform voltage measurement at C-04 combination meter connector.

Disconnect connector, and measure at the harness side.

Ignition switch: ON

Voltage between terminal No. 42 and earth.

OK: System voltage

Q: Is the check result normal?

YES: Go to Step 6

.
NO: Go to Step 5

STEP 5: Connector check: C-303 ignition switch connector

Q: Is the check result normal?

YES:

Check intermediate connectors C-203 and C-205, and repair if necessary. If intermediate connectors are normal, check and repair harness between C-04 (terminal No. 42) combination meter connector and C-303 (terminal No. 2) ignition switch connector.

Check power supply line for open/short circuit.

NO: Repair

STEP 6: Connector check: C-134 engine-A/T-ECU connector

Q: Is the check result normal?

YES: Go to Step 7

.
NO: Repair.

STEP 7: Perform voltage measurement at C-134 engine-A/T-ECU connector.

Disconnect connector, and measure at the harness side.

Ignition switch: ON

Voltage between terminal No. 7 and earth.

OK: System voltage

Q: Is the check result normal?

YES: Go to Step 9

.
NO:

Go to Step 8 .

STEP 8: Check connector: C-05 combination meter connector

Q: Is the check result normal?

YES:

Check intermediate connector C-105, and repair if necessary. If intermediate connector is normal, check and repair harness between C-05 (terminal No. 14) combination meter connector and C-134 (terminal No. 7) engine-A/T-ECU connector.

Check output line for open/short circuit.

NO: Repair

STEP 9: Connector check: C-303 ignition switch connector

Q: Is the check result normal?

YES: Go to Step 10

.
NO: Repair.

STEP 10: Check harness between C-04 (terminal No. 42) combination meter connector and C-303 (terminal No. 2) ignition switch connector.

NOTE: Before checking harness, check intermediate connectors C-203 and C-205, and repair if necessary.

Check power supply line for damage.

Q: Is the check result normal?

YES: Go to Step 11

.
NO: Repair.

STEP 11: Connector check: C-05 ignition switch connector

Q: Is the check result normal?

YES: Go to Step 12

.
NO: Repair.

STEP 12: Check harness between C-05 (terminal No. 14) combination meter connector and C-134 (terminal No. 7) engine-A/T-ECU connector.

NOTE: Before checking harness, check intermediate connector C-105, and repair if necessary.

Check output line for damage.

Q: Is the check result normal?

YES: Go to Step 13

.
NO: Repair.

STEP 13: Check the trouble symptoms.

Q: Does trouble symptom persist?

YES: Replace engine-A/T-ECU.
NO: Intermittent malfunction (Refer to GROUP 00 - How to Use Troubleshooting/Inspection Service Points


Inspection Procedure 3: The Engine Warning Lamp Does Not Illuminate Right after the Ignition Switch is Turned the "ON" Position

OPERATION Battery voltage is applied to engine warning lamp of combination meter connector (terminal No. 42) from ignition switch. Engine-A/T-ECU (terminal No. 7) makes power transistor in unit be in "ON" position, and that makes currents go on engine warning lamp of combination meter connector (terminal No. 14).
COMMENTS ON TROUBLE SYMPTOM Engine-A/T-ECU turns on engine warning lamp for 5 seconds to check for burnt-out bulb immediately after ignition switch is turned to ON. If engine warning lamp is not lit just after turning ignition switch to "ON" position, failure is possibly caused by burn-out bulb, open/short circuit or other faults.
PROBABLE CAUSE Engine warming lamp bulb burnt out Failed ignition switch Open/short circuit in engine warning lamp circuit for or loose connector contact Failed engine-A/T-ECU
	DIAGNOSIS PROCEDURE

	STEP 1: Check engine start-up. Q: Is engine started? YES: Go to Step 2 . NO: Check engine-A/T-ECU power supply, engine control relay and ignition switch IG1 system (Refer to Inspection Procedure 24 ).
	STEP 2: Check engine warning lamp for burnt-out bulb. Q: Is the check result normal? YES: Go to Step 3 . NO: Replace engine warning lamp.
	STEP 3: Connector check: C-04 combination meter connector
	Q: Is the check result normal? YES: Go to Step 4 . NO: Repair.
	STEP 4: Perform voltage measurement at C-04 combination meter connector.
	Disconnect connector, and measure at the harness side. Ignition switch: ON Voltage between terminal No. 42 and earth. OK: System voltage Q: Is the check result normal? YES: Go to Step 6 . NO: Go to Step 5 .
	STEP 5: Connector check: C-303 ignition switch connector
	Q: Is the check result normal? YES: Check intermediate connectors C-203 and C-205, and repair if necessary. If intermediate connectors are normal, check and repair harness between C-04 (terminal No. 42) combination meter connector and C-303 (terminal No. 2) ignition switch connector. Check power supply line for open/short circuit. NO: Repair
	STEP 6: Connector check: C-134 engine-A/T-ECU connector
	Q: Is the check result normal? YES: Go to Step 7 . NO: Repair.
	STEP 7: Perform voltage measurement at C-134 engine-A/T-ECU connector.
	Disconnect connector, and measure at the harness side. Ignition switch: ON Voltage between terminal No. 7 and earth. OK: System voltage Q: Is the check result normal? YES: Go to Step 9 . NO: Go to Step 8 .
	STEP 8: Check connector: C-05 combination meter connector
	Q: Is the check result normal? YES: Check intermediate connector C-105, and repair if necessary. If intermediate connector is normal, check and repair harness between C-05 (terminal No. 14) combination meter connector and C-134 (terminal No. 7) engine-A/T-ECU connector. Check output line for open/short circuit. NO: Repair
	STEP 9: Connector check: C-303 ignition switch connector
	Q: Is the check result normal? YES: Go to Step 10 . NO: Repair.
	STEP 10: Check harness between C-04 (terminal No. 42) combination meter connector and C-303 (terminal No. 2) ignition switch connector.
	NOTE: Before checking harness, check intermediate connectors C-203 and C-205, and repair if necessary. Check power supply line for damage. Q: Is the check result normal? YES: Go to Step 11 . NO: Repair.
	STEP 11: Connector check: C-05 ignition switch connector
	Q: Is the check result normal? YES: Go to Step 12 . NO: Repair.
	STEP 12: Check harness between C-05 (terminal No. 14) combination meter connector and C-134 (terminal No. 7) engine-A/T-ECU connector.
	NOTE: Before checking harness, check intermediate connector C-105, and repair if necessary. Check output line for damage. Q: Is the check result normal? YES: Go to Step 13 . NO: Repair.
	STEP 13: Check the trouble symptoms. Q: Does trouble symptom persist? YES: Replace engine-A/T-ECU. NO: Intermittent malfunction (Refer to GROUP 00 - How to Use Troubleshooting/Inspection Service Points ).