Charging System: Testing and Inspection
ON-VEHICLE INSPECTIONCAUTION:
- Check that the battery cables are connected to the correct terminals.
- Disconnect the battery cables when the battery is charged quickly.
- Do not perform tests with a high voltage Insulation resistance tester.
- Never disconnect the battery while the engine is running.
- Do not check whether the alternator generates or not, with connecting terminal F to the other terminal.
- Check that the charging cable is tightened on terminal B of the alternator and the fuse box.
1. CHECK BATTERY ELECTROLYTE LEVEL
a. Check the electrolyte quantity of each cell.
Maintenance-free Battery:
If it is under the lower level, replace the battery.
Except Maintenance-free Battery:
If it is under the lower level, add distilled water.
2. Except Maintenance-free Battery:
CHECK BATTERY SPECIFIC GRAVITY
a. Check the specific gravity of each cell.
Standard specific gravity: 1.25-1.29 at 20°C (68°F)
If the specific gravity is less than the specification, charge the battery.
3. Maintenance-free Battery:
CHECK BATTERY VOLTAGE
a. After the vehicle has run for 20 minutes, stop the engine.
b. Turn the ignition switch ON, and operate the headlight, blower fan and defogger for 1 minute.
c. Turn the ignition switch OFF.
d. Measure the battery voltage.
Standard voltage: 12.5 - 12.9 V at 20°C (68°F)
If the voltage is less than specification, charge the battery.
4. CHECK BATTERY TERMINALS, FUSIBLE LINK AND FUSES
a. Check that the battery terminals are not loose or corroded.
If the terminals are corroded, clean the terminals.
b. Check the fusible link, H-fuses and fuses for continuity.
5. INSPECT DRIVE BELT
a. Visually check the belt for excessive wear, frayed cords etc.
If any defect has been found, replace the drive belt.
HINT: 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 it fits properly in the ribbed grooves.
HINT: Check with your hand to confirm that the belt has not slipped out of the groove on the bottom of the pulley.
6. VISUALLY CHECK ALTERNATOR WIRING
a. Check that the wiring is in good condition.
7. LISTEN FOR ABNORMAL NOISES FROM ALTERNATOR
a. Check that there is no abnormal noise from the alternator while the engine is running.
8. CHECK DISCHARGE WARNING LIGHT CIRCUIT
a. Warm up engine and then turn it off.
b. Switch off all accessories.
c. Turn the ignition switch ON. Check that the discharge warning light is lit.
d. Start the engine. Check that the light goes off.
If the light does not go off as specified, troubleshoot the charge warning light circuit.
9. INSPECT CHARGING CIRCUIT WITHOUT LOAD
HINT: If a battery/alternator tester is available, connect the tester to the charging circuit as per manufacturer's instructions.
a. If a tester is not available, connect a voltmeter to the charging circuit as follows.
1. Disconnect the wire from terminal B of the alternator, and connect it to the negative (-) tester probe of the ammeter.
2. Connect the positive (+) tester probe of the ammeter to terminal B of the alternator.
3. Connect the positive (+) tester probe of the voltmeter to terminal B of the alternator.
4. Ground the negative (-) tester probe of the voltmeter.
b. Check the charging circuit as follows.
1. With the engine running from idling to 2,000 rpm, check the reading on the ammeter and voltmeter.
Standard amperage: 10 A or less Standard voltage: 13.2 - 14.8 V
10. INSPECT CHARGING CIRCUIT WITH LOAD
a. With the engine running at 2,000 rpm, turn on the high beam headlights and place the heater blower switch at "HI".
b. Check the reading on the ammeter.
Standard amperage: 30 A or more
If the ammeter reading is less than standard amperage, repair the alternator.