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On-Vehicle Inspection

  1. CHECK BATTERY CONDITION 
    NOTE:

    If the battery is weak or if the engine is difficult to start, perform the following procedures.

    1. Check the battery for damage and deformation. If damage, deformation or leakage is found, replace the battery.
    2. Check the electrolyte quantity of each cell.
      1. For maintenance-free batteries:
        • If the electrolyte quantity is below the lower line, replace the battery.
        • If the electrolyte quantity is above the lower line, check the battery voltage when cranking the engine. If the voltage is less than 9.6 V, recharge or replace the battery.

          HINT: 

          Before checking the battery voltage, turn off all the electrical systems (headlights, blower motor, rear defogger, etc.).

      2. For non-maintenance-free batteries:
        • If the electrolyte quantity is below the lower line, add distilled water to each cell. Then, recharge the battery and check the electrolyte specific gravity.

          Standard specific gravity

          1.25 to 1.29 at 20°C (68°F)

        • If the electrolyte quantity is above the lower line, check the battery voltage when cranking the engine. If the voltage is less than 9.6 V, recharge or replace the battery.

          HINT: 

          Before checking the battery voltage, turn off all the electrical systems (headlights, blower motor, rear defogger, etc.).

    3. Check the voltage.
      1. Turn the engine switch off and turn on the headlights for 20 to 30 seconds. This will remove the surface charge from the battery.
      2. Measure the battery voltage according to the value(s) in the table below.

        Standard Voltage

        Tester Connection Condition Specified Condition
        Positive (+) terminal - Negative (-) terminal 20°C (68°F) 12.5 to 12.9 V

        HINT: 

        If the voltage is not as specified, charge the battery.

  2. CHECK BATTERY TERMINAL AND FUSE 
    1. Check that the battery terminals are not loose or corroded.

      If the terminals are corroded, clean the terminals.

    2. Measure the resistance of the charging fuses.

      Standard resistance

      Below 1 Ω

      If the result is not as specified, replace fuses as necessary.

  3. CHECK V-RIBBED BELT 
    1. Check the belt for wear, cracks or other signs of damage.
      Fig 1: View Of Checking Drive Belt For Excessive Wear
      GTY104483Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      If any of the following defects is found, replace the V-ribbed belt.

      HINT: 

      • The belt is cracked.
      • The belt is worn out to the extent that the cords are exposed.
      • The belt has chunks missing from the ribs.
    2. Check that the belt fits properly in the ribbed grooves.
      Fig 2: View Of Correct And Incorrect Ribbed Grooves
      GTY104525Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      HINT: 

      Check with your hand to confirm that the belt has not slipped out of the groove on the bottom to the pulley. If it has slipped out, replace the V-ribbed belt. Install a new V-ribbed belt correctly.

  4. VISUALLY CHECK GENERATOR WIRING 
    1. Check that the wiring is in good condition.

      If damaged, repair or replace the generator wire.

  5. LISTEN FOR ABNORMAL NOISE FROM GENERATOR 
    1. Check that the generator does not emit any abnormal noise while the engine is running.

      If there is abnormal noise, replace the pulley or generator.

  6. CHECK CHARGE WARNING LIGHT CIRCUIT 
    1. Turn the engine switch on (IG). Check that the charge warning light turns on.
    2. Start the engine and check that the light turns off.

      If the light does not operate as specified, troubleshoot the charge warning light circuit.

  7. CHECK CHARGING CIRCUIT WITHOUT LOAD 
    Fig 3: Inspecting Charging Circuit Without Load
    GTY142905Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Check the charging circuit.
      1. Put the vehicle in a no-load test condition and run the engine at 2000 rpm. Using a voltmeter and ammeter, measure the battery voltage and amperage.

        Standard amperage

        10 A or less

        Standard voltage

        13.2 to 14.8 V

        If the results are not as specified, replace the generator.

        HINT: 

        If the battery is not fully charged, the ammeter reading will sometimes be more than the standard amperage.

  8. CHECK CHARGING CIRCUIT WITH LOAD 
    1. Put the vehicle in a load test condition (set the headlights to high beam and set the heater blower switch to Hi) and run the engine at 2000 rpm. Using an ammeter, measure the amperage.
    2. Check the reading on the ammeter.

      Standard amperage

      30 A or more

      If the ammeter reading is less than the standard amperage, replace the generator.

      HINT: 

      • If the ammeter reading is less than the standard amperage even though the battery is fully charged, the load is not sufficient. Therefore, operate the wiper motor, rear window defogger, etc. to increase the load, and perform the measurement again.
      • If the battery is fully charged, the ammeter reading will sometimes be less than the standard amperage.