FixVault

On-Vehicle Inspection

CAUTION:
  • Never disconnect the battery while the engine is running.
  • Check that the battery cables are correctly connected to the terminals.
  • Do not connect the battery cables during quick charging.
  1. Inspection of the battery fluid level
    1. Fluid level inspection
      1. If the level is below LOW, either replace the battery or replenish the level by pouring in distilled water.
  2. Checking of the battery specific gravity
    1. Check the specific gravity of the fluid in each battery cell.

      Standard value: 1.25 - 1.29 (At fluid temperature of 20°C {68°F})

      NOTE: If this is less than the standard value, recharge the battery.
      Fig 1: Checking Battery Specific Gravity
      G08557289Courtesy of SUBARU OF AMERICA, INC.
  3. Battery voltage check
    1. In order to remove the surface charge, with the ignition turned to IG OFF, turn the headlight switch to ON for approximately 20 to 30 seconds.
    2. Turn the headlight switch to OFF.
    3. Measure the battery voltage between terminals.

      Voltage

      VOLTAGE SPECIFICATION

      Inspection terminals Inspection conditions Standard value
      Positive battery terminal - Negative battery terminal Fluid temperature 20°C {68°F} 12.5 - 12.9 V
      NOTE: If this is less than the standard value, recharge the battery.
      Fig 2: Measuring Battery Voltage Between Terminals
      G08557290Courtesy of SUBARU OF AMERICA, INC.
  4. Inspection of the battery terminals, fusible links, and fuses
    1. Check that the battery terminals are not loose or corroded.
    2. Check that there is continuity through the fusible links and fuses.
  5. Checking of the fan & alternator V-belt
    NOTE: Only perform this inspection if you plan on reusing it. (Refer to ON-VEHICLE INSPECTION )
  6. Inspection of the alternator wiring harness
    1. Check that there are no cracks or deterioration in the wiring harness.
  7. Checking for strange noises originating from the alternator
    1. Check that no strange noises come from the alternator during engine starting.
  8. Inspection of the charge warning light
    1. Warm up the engine and turn the ignition to IG OFF.
    2. Turn all of the electrical device switches to OFF.
    3. Turn the ignition to IG ON and confirm that the charge warning light illuminates.
    4. Confirm that this light turns off after starting the engine.
      NOTE: If the light does not behave as specified above, perform troubleshooting for the charge warning light circuit.
  9. No load test
    1. Inspection of the charging circuit
      1. When under no load, measure the battery voltage when the engine speed is increased up to 2000 r/min.

        Voltage

        VOLTAGE SPECIFICATION

        Inspection terminals Inspection conditions Standard value
        B terminal - Chassis ground 20 A or less 11.3 - 15.6 V
        Fig 3: Inspecting Charging Circuit (No Load Test)
        G10215861Courtesy of SUBARU OF AMERICA, INC.
  10. Load test
    1. Start under the same conditions as the no load test, turn the headlights to high beam and the heater blower switch to Hi and immediately measure the current when the engine speed reaches 2000 r/min.

      Current value

      BATTERY CURRENT VALUE SPECIFICATION

      Inspection terminals Inspection conditions Standard value
      B terminal - Positive battery terminal Always 30 A or more
      Fig 4: Inspecting Charging Circuit (Load Test)
      G10215862Courtesy of SUBARU OF AMERICA, INC.
      NOTE: If the battery is fully charged even though a current is shown that is at the standard value or less, as the current becomes small, operate other devices such as the wiper motor or the rear window defogger to increase the load and perform the measurement again.
  11. Inspection of the charging control system
    1. Inspection of the wiring harness
      1. Disconnect the engine control computer connector A35.
      2. Disconnect the alternator assembly connector A43.
      3. Measure the resistance between the terminals.

        Resistance (open circuit check)

        RESISTANCE SPECIFICATION

        Inspection terminals (Terminal symbol) Inspection conditions Standard value
        A35-18 (ALT) - A43-3 (M) Always Less than 1 Ω

        Resistance (short circuit check)

        RESISTANCE SPECIFICATION

        Inspection terminals (Terminal symbol) Inspection conditions Standard value
        A35-18 (ALT) and A43-3 (M) - Between other terminals or the chassis ground Always 10 kΩ or more
    2. Inspection of the engine control computer
      1. Start the engine and wait 20 to 30 minutes for it to warm up.
      2. Connect the SSM3 between engine control computer connectors A35-18 (ALT) and A34-1 (E03).
        NOTE: This inspection is performed from the back side of the connector with the connector in a connected state.
      3. Confirm that the engine control computer output while the vehicle is idling has the same square waveform as shown in Fig 5.
        Item Contents
        Measured terminal (terminal code) A35-18 (ALT) - A34-1 (E03)
        Equipment setting 2 V/DIV, 2 ms/DIV
        Condition Idling
        NOTE:
        • This oscilloscope waveform is an example for reference and has had noise and chattering removed.
        • As the duty ratio can vary depending on the electrical load and battery conditions, a constant value is not output.
        Fig 5: Engine Control Computer Output Signal Waveform
        G10215863Courtesy of SUBARU OF AMERICA, INC.