Charging System: Testing and Inspection
ON-VEHICLE INSPECTION1. CHECK BATTERY VOLTAGE (MAINTENANCE-FREE BATTERY)
a. If it has been less than 20 minutes since you stopped driving the vehicle, turn the ignition switch ON and turn on the electrical systems (headlight, blower motor, rear defogger etc.) for 60 seconds to remove the surface charge.
b. Turn the ignition switch OFF and turn off the electrical systems.
c. Measure the battery voltage between the negative (-) and positive (+) terminals of the battery.
Standard voltage: 12.5 to 12.9 V at 20 °C (68 °F)
HINT: If the voltage is less than the specified range, charge the battery.
d. Check the indicator as shown in the illustration.
2. CHECK BATTERY TERMINALS, FUSIBLE LINK AND FUSES
a. Check that the battery terminals are not loose or corroded.
b. Check the fusible link, H-fuses and fuses for continuity.
3. INSPECT DRIVE BELT
a. Visually check the belt for excessive wear, frayed cords etc.
HINT:
- If any defect are found, replace the drive belt.
- Cracks on the rib side of a belt are considered acceptable. If the belt has chunks missing from the ribs, it should be replaced.
b. Check that the belt fits properly in the ribbed grooves.
HINT: Confirm that the belt has not slipped out of the grooves on the bottom of the pulley.
4. VISUALLY CHECK ALTERNATOR WIRING
a. Check that the wiring is in good condition.
5. LISTEN FOR ABNORMAL NOISES FROM ALTERNATOR
a. Check that no abnormal noises are heard from the generator while the engine is running.
6. INSPECT CHARGE WARNING LIGHT CIRCUIT
a. Turn the ignition switch ON. Check that the charge warning light comes on.
b. Start the engine. Check that the light goes off.
HINT: If the light does not operate as specified, troubleshoot the charge warning light circuit.
7. INSPECT CHARGING CIRCUIT WITHOUT LOAD
a. If a battery/alternator tester is available, connect the tester to the charging circuit as per manufacturer's instructions.
b. If a tester is not available, connect a voltmeter to the charging circuit as follows.
1. Disconnect to the wire from terminal B of the generator and connect it to the negative (-) lead of the ammeter.
2. Connect the positive (+) lead of the ammeter to terminal B of the generator.
3. Connect the positive (+) lead of the voltmeter to terminal B of the generator.
4. Ground the negative (-) lead of the voltmeter.
c. Check the charging circuit.
1. With the engine running from idle to 2,000 rpm, check the reading on the ammeter and voltmeter.
Standard amperage: 10 A or less
Standard voltage: 12.9 to 14.9 V
8. INSPECT CHARGING CIRCUIT WITH LOAD
a. With the engine running at 2,000 rpm, turn on the high beam headlights and turn the heater blower switch at "HI".
b. Check the reading on the ammeter.
Standard amperage: 30 A or more
HINT:
- If the ammeter reading is less than standard amperage, repair the generator.
- If the battery is fully charged, the indication will sometimes be less than standard amperage.