Inspection Procedure 26
INSPECTION PROCEDURE 26: Generator output voltage is low (approximately 12.3 volts).Generator Circuit Part 1:
Generator Circuit Part 2:
CIRCUIT OPERATION
- The ECM
TROUBLESHOOTING HINTS (The most likely causes for this charging system:)
- Malfunction of the charging system.
- Short circuit in harness between generator G terminal and ECM
- ECM failed.
- PCM failed.
DIAGNOSIS
STEP 1. Measure the voltage at generator intermediate connector B-14 by backprobing.
1. Do not disconnect the connector B-14.
2. Start the engine and run at idle.
3. Measure the voltage between terminal No. 6 and ground by backprobing.
a. Engine: warming up
b. Radiator fan: stopped
c. Headlight switch: OFF to ON
d. Rear defogger switch: OFF to ON
e. Stoplight switch: OFF to ON
- Voltage rises by 0.2 - 3.5 volts.
4. Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is the measured voltage within the specified range?
YES: Go to Step 2.
NO: Replace the generator. Then confirm that the malfunction symptom is eliminated.
STEP 2. Check connector B-14 at generator intermediate connector for damage.
Q: Is the connector in good condition?
YES: Go to Step 3.
NO: Repair or replace it. Then confirm that the malfunction symptom is eliminated.
STEP 3. Check connector B-25 at generator connector for damage.
Q: Is the connector in good condition?
YES: Go to Step 4.
NO: Repair or replace it. Then confirm that the malfunction symptom is eliminated.
STEP 4. Check connector C-135 at ECM
Q: Is the connector in good condition?
YES: Go to Step 5.
NO: Repair or replace it. Then confirm that the malfunction symptom is eliminated.
STEP 5. Check for open circuit and short circuit to ground and harness damage between generator connector B-25 (terminal No. 1) and ECM connector C-135
NOTE: Check harness after checking intermediate connector B-14. If intermediate connector is damaged, repair or replace it. Then check that, the malfunction is eliminated.
Q: Is the harness wire in good condition?
YES: Replace the ECM or the PCM. Then confirm that the malfunction symptom is eliminated.
NO: Repair it. Then confirm that the malfunction symptom is eliminated.