2021 Mazda 3 BaseFACTORY OEM SERVICE PROCEDURE

Generator current inspection

NOTE:
  • Since the charging current decreases rapidly after starting the engine, carry out the following procedure quickly, and read the maximum current value.
  1. Verify that the battery is fully charged. (See BATTERY INSPECTION (US) .)
  2. Verify that the assembly condition of the drive belt is normal. (See DRIVE BELT INSPECTION (VIN M) .)
  3. Disconnect the negative battery terminal. (See NEGATIVE BATTERY TERMINAL DISCONNECTION/CONNECTION (US) .)
  4. Connect a tester, which can read 120 A or more, between generator terminal B and generator terminal B cable.
  5. Connect the negative battery terminal. (See NEGATIVE BATTERY TERMINAL DISCONNECTION/CONNECTION (US) .)
  6. Turn off all electrical loads.
  7. Start the engine.
  8. Increase engine speed to 2, 500 rpm.
    NOTE:
    • When the electrical load on the vehicle is low, the specified current cannot be verified although the generator is normal. In this case, increase the electrical load (Leave the headlights turned on for a while, then discharge the battery, or use a similar method.) and recheck.
    • If the generator itself or the ambient temperature are too high, the specified current also cannot be verified. In this case, cool down the generator and recheck.
  9. With the electric loads such as headlights, blower motor, rear window defogger, brake lights turned on, verify that the current increases.

    Generator generated current minimum value 

    70% of the nominal output current (nominal output current: 130 A)

    [Ambient temp. 20°C {68°F}, voltage 13.0-15.0 V, both engine and generator are hot]

Factory Service Tools

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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • • You smell fuel, burning insulation, or see smoke.
  • • Brakes feel soft, pull hard to one side, or make grinding noises.
  • • The engine overheats, stalls repeatedly, or misfires under load.
  • • You are missing required tools, torque specs, or safe lifting equipment.
  • • You are not confident in the next step or safety outcome.