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On-Vehicle Inspection

CAUTION:
  • Check that the battery cables are connected to the correct terminals.
  • Disconnect the battery cables when the battery is given a quick charge.
  • Do not perform tests with a high voltage insulation resistance tester.
  • Never disconnect the battery while the engine is running.
  1. CHECK BATTERY ELECTROLYTE LEVEL 

    Check the electrolyte quantity of each cell.

    If under the lower level, replace the battery (or add distilled water if possible). Check the charging system.

  2. Except Maintenance-Free Battery: CHECK BATTERY SPECIFIC GRAVITY 

    Check the specific gravity of each cell.

    1. Standard specific gravity: 1.25-1.29 at 20°C (68°F) 

    If the specific gravity is less than specification, charge the battery.

    Fig 1: Checking Battery Specific Gravity
    G01331436Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  3. Maintenance-Free Battery: CHECK BATTERY VOLTAGE 
    1. After having driven the vehicle and in the case that 20 minutes have not passed after having stopped the engine, turn the ignition switch ON and turn on the electrical system (headlight, blower motor, rear defogger etc.) for 60 seconds to remove the surface charge.
    2. Turn the ignition switch OFF and turn off the electrical systems.
      Fig 2: Checking Battery Voltage
      G01331437Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    3. Measure the battery voltage between the negative (-) and positive (+) terminals of the battery.
      1. Standard voltage: 12.5 -12.9 V at 20°C (68°F) 

    If the voltage is less than specification, charge the battery.

    HINT:

    Check the indicator as shown in Fig 3.

  4. CHECK BATTERY TERMINALS, FUSIBLE LINK AND FUSES 
    1. Check that the battery terminals are not loose or corroded.

      If the terminals are corroded, clean the terminals.

    2. Check the fusible link, H-fuses, M-fuse and fuses for continuity.
      Fig 3: Checking Indicator
      G01331438Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  5. INSPECT DRIVE BELTS 
    1. Visually check the drive 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 drive belt are considered acceptable. If the drive belt has chunks missing from the ribs, it should be replaced.

      Fig 4: Checking Drive Belt For Excessive Wear
      G01331439Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Using a belt tension gauge, measure the belt tension.

      Belt tension gauge:

      1. DENSO BTG-20 (95506-00020)
      2. Burroughs No. BT-33-73F

      Drive belt tension: 

      Fig 5: Drive Belt Tension
      G01331440Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      If the belt tension is not as specified, adjust it.

      Fig 6: Measuring Belt Tension
      G01331441Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      HINT:

      • "New belt" refers to a belt which has been used less than 5 minutes on a running engine.
      • "Used belt" refers to a belt which has been used on a running engine for 5 minutes or more.
        Fig 7: Identifying Correct Placement Of Belt On Groove
        G01331442Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      • After installing a belt, check that it fits properly in the ribbed grooves.
      • Check with your hand to confirm that the belt has not slipped out of the groove on the bottom of the pulley.
      • After installing a new belt, run the engine for about 5 minutes and recheck the belt tension.
  6. VISUALLY CHECK GENERATOR WIRING AND LISTEN FOR ABNORMAL NOISES 
    1. Check that the wiring is in good condition.
    2. Check that there is no abnormal noise from the generator while the engine is running.
  7. CHECK DISCHARGE WARNING LIGHT CIRCUIT 
    1. Warm up the engine and then turn it off.
    2. Switch off all accessories.
    3. Turn the ignition switch "ON". Check that the discharge warning light is lit.
    4. Start the engine. Check that the light goes off.

    If the light does not go off as specified, troubleshoot the discharge light circuit.

  8. INSPECT CHARGING CIRCUIT WITHOUT LOAD 

    HINT:

    If a battery/generator tester is available, connect the tester to the charging circuit as per manufacturer's instructions.

    1. If a tester is not available, connect a voltmeter and ammeter to the charging circuit as follows:
      • Disconnect the wire from terminal B of the generator, and connect it to the negative (-) tester probe of the ammeter.
      • Connect the positive (+) tester probe of the ammeter to terminal B of the generator.
      • Connect the positive (+) tester probe of the voltmeter to terminal B of the generator.
      • Ground the negative (-) tester probe of the voltmeter.
      Fig 8: Inspecting Charging Circuit Without Load
      G01331443Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Check the charging circuit as follows:

      With the engine running from idling to 2,000 rpm, check the reading on the ammeter and voltmeter.

      1. Standard amperage: 10 A or less 

      Standard voltage: 

      1. 13.5-15.1 V for L3B type 
      2. 13.2-14.0 V for SC1 type 

    If the voltmeter reading is more than standard voltage, replace the voltage regulator (L3B type) or coil assembly (SC1 type).

  9. INSPECT CHARGING CIRCUIT WITH LOAD 
    1. With the engine running at 2,000 rpm, turn on the high beam headlights and place the heater blower switch at "HI".
    2. Check the reading on the ammeter.
      1. Standard amperage: 30 A or more 

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

    HINT:

    If the battery is fully charged, the indication will sometimes be less than standard amperage.

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