Inspection Procedure 19: Battery Rundown

COMMENT ON TROUBLE SYMPTOM

Failure is possibly caused by failed alternator, failed generation control circuit or other faults.

PROBABLE CAUSE

Failed battery

G terminal short-circuited

Failed alternator

Failed engine-A/T-ECU

DIAGNOSIS PROCEDURE

STEP 1. Check battery voltage.

Measure battery voltage during cranking.

OK: 8 V or more

Q: Is the check result normal?

YES: Go to Step 2

.
NO: Check battery (Refer to GROUP 54A - Battery - On-vehicle Service - Battery Test

STEP 2. Connector check: B-19 intermediate connector

Q: Is the check result normal?

YES: Go to Step 3

.
NO: Repair.

STEP 3. Perform voltage measurement at B-19 intermediate connector.

Disconnect connector, and measure at male connector side.

Ignition switch: ON

Voltage between terminal No. 5 and earth.

OK: Battery voltage

Q: Is the check result normal?

YES: Go to Step 5

.
NO: Go to Step 4

STEP 4. Connector check: C-303 ignition switch connector

Q: Is the check result normal?

YES:

Check intermediate connectors C-04, C-05, C-105, C-203 and C-205, and repair if necessary. If intermediate connectors are normal, check and repair harness between B-19 (terminal No. 5) intermediate connector and C-303 (terminal No. 2) ignition switch connector.

Check power supply line for open/short circuit.

NO: Repair.

STEP 5. Perform voltage measurement at B-19 intermediate connector.

Disconnect connector, and measure at female connector side.

Ignition switch: ON

Voltage between terminal No. 4 and earth.

OK: Battery voltage

Q: Is the check result normal?

YES: Go to Step 10

.
NO: Go to Step 6

STEP 6. Connector check: B-30 alternator connector

Q: Is the check result normal?

YES: Go to Step 7

.
NO: Repair.

STEP 7. Check harness between B-19 (terminal No. 4) intermediate connector and B-30 (terminal No. 1) alternator connector.

Check output line for short circuit.

Q: Is the check result normal?

YES: Go to Step 8

.
NO: Repair.

STEP 8. Check harness between B-19 (terminal No. 5) intermediate connector and B-30 (terminal No. 3) alternator connector.

Check power supply line for open/short circuit.

Q: Is the check result normal?

YES: Go to Step 9

.
NO: Repair.

STEP 9. Check harness between B-30 (terminal No. 3) alternator connector and C-303 (terminal No. 2) ignition switch connector.

NOTE: Before checking harness, check intermediate connectors C-04, C-05, C-105, C-203 and C-205, and repair if necessary.

Check power supply line for damage.

Q: Is the check result normal?

YES: Replace alternator.
NO: Repair.

STEP 10. Connector check: C-112 engine-A/T-ECU connector

Q: Is the check result normal?

YES: Go to Step 11

.
NO: Repair.

STEP 11. Perform voltage measurement at C-112 engine-A/T-ECU connector.

Disconnect connector, and measure at harness side.

Ignition switch: ON

Voltage between terminal No. 8 and earth.

OK: System voltage

Q: Is the check result normal?

YES: Go to Step 12

.
NO:

Check and repair harness between B-19 (terminal No. 4) intermediate connector and C-112 (terminal No. 8) engine-A/T-ECU connector.

Check output line for short circuit.

STEP 12. Perform voltage measurement at C-112 engine-A/T-ECU connector.

Measure engine-A/T-ECU terminal voltage.

Engine: Idling after warm-up

Selector lever position: P

Radiator fan: Inactive

Voltage between terminal No. 8 and earth.

OK: Switching the headlamps to ON from OFF causes the voltage to increase by 0.2 - 3.5 V.

Q: Is the check result normal?

YES: Go to Step 13

.
NO:

Check alternator.

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 19: Battery Rundown

COMMENT ON TROUBLE SYMPTOM Failure is possibly caused by failed alternator, failed generation control circuit or other faults.
PROBABLE CAUSE Failed battery G terminal short-circuited Failed alternator Failed engine-A/T-ECU
	DIAGNOSIS PROCEDURE

	STEP 1. Check battery voltage. Measure battery voltage during cranking. OK: 8 V or more Q: Is the check result normal? YES: Go to Step 2 . NO: Check battery (Refer to GROUP 54A - Battery - On-vehicle Service - Battery Test ).
	STEP 2. Connector check: B-19 intermediate connector
	Q: Is the check result normal? YES: Go to Step 3 . NO: Repair.
	STEP 3. Perform voltage measurement at B-19 intermediate connector.
	Disconnect connector, and measure at male connector side. Ignition switch: ON Voltage between terminal No. 5 and earth. OK: Battery voltage Q: Is the check result normal? YES: Go to Step 5 . NO: Go to Step 4 .
	STEP 4. Connector check: C-303 ignition switch connector
	Q: Is the check result normal? YES: Check intermediate connectors C-04, C-05, C-105, C-203 and C-205, and repair if necessary. If intermediate connectors are normal, check and repair harness between B-19 (terminal No. 5) intermediate connector and C-303 (terminal No. 2) ignition switch connector. Check power supply line for open/short circuit. NO: Repair.
	STEP 5. Perform voltage measurement at B-19 intermediate connector.
	Disconnect connector, and measure at female connector side. Ignition switch: ON Voltage between terminal No. 4 and earth. OK: Battery voltage Q: Is the check result normal? YES: Go to Step 10 . NO: Go to Step 6 .
	STEP 6. Connector check: B-30 alternator connector
	Q: Is the check result normal? YES: Go to Step 7 . NO: Repair.
	STEP 7. Check harness between B-19 (terminal No. 4) intermediate connector and B-30 (terminal No. 1) alternator connector.
	Check output line for short circuit. Q: Is the check result normal? YES: Go to Step 8 . NO: Repair.
	STEP 8. Check harness between B-19 (terminal No. 5) intermediate connector and B-30 (terminal No. 3) alternator connector.
	Check power supply line for open/short circuit. Q: Is the check result normal? YES: Go to Step 9 . NO: Repair.
	STEP 9. Check harness between B-30 (terminal No. 3) alternator connector and C-303 (terminal No. 2) ignition switch connector.
	NOTE: Before checking harness, check intermediate connectors C-04, C-05, C-105, C-203 and C-205, and repair if necessary. Check power supply line for damage. Q: Is the check result normal? YES: Replace alternator. NO: Repair.
	STEP 10. Connector check: C-112 engine-A/T-ECU connector
	Q: Is the check result normal? YES: Go to Step 11 . NO: Repair.
	STEP 11. Perform voltage measurement at C-112 engine-A/T-ECU connector.
	Disconnect connector, and measure at harness side. Ignition switch: ON Voltage between terminal No. 8 and earth. OK: System voltage Q: Is the check result normal? YES: Go to Step 12 . NO: Check and repair harness between B-19 (terminal No. 4) intermediate connector and C-112 (terminal No. 8) engine-A/T-ECU connector. Check output line for short circuit.
	STEP 12. Perform voltage measurement at C-112 engine-A/T-ECU connector.
	Measure engine-A/T-ECU terminal voltage. Engine: Idling after warm-up Selector lever position: P Radiator fan: Inactive Voltage between terminal No. 8 and earth. OK: Switching the headlamps to ON from OFF causes the voltage to increase by 0.2 - 3.5 V. Q: Is the check result normal? YES: Go to Step 13 . NO: Check alternator.
	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 ).