Generator Inspection: Generator: Current

2010 Mazda 5 Sport, 2.3 L, StandardSECTION Current
WARNING: This page is about a different car, the 2005 Mazda RX-8 and 2004 Mazda RX-8. However, it is still accessible from the selected car via links, so may be relevant.
  1. Verify that the battery is fully charged.
  2. Verify that the drive belt deflection/tension is within the specification. (See DRIVE BELT DEFLECTION/TENSION INSPECTION .)
  3. Disconnect the negative battery cable.
  4. Connect a tester capable of reading 120 A or above  between generator terminal B and the wiring harness.
  5. Connect the negative battery cable.
  6. Turn off all electrical loads.
  7. Start the engine.
  8. Increase engine speed from 2,000-2,500 RPM. 
  9. Turn the following electrical loads on and verify that the current reading increases.
    • Headlights
    • Blower motor
    • Rear window defroster
    NOTE:
    • Current required for generating power varies with electrical loads applied.

Reference value 

Current possible for power generation (differs according to load) 

[Conditions] ambient temperature 20°C {68 °F}, voltage 13.0-15.0 V, engine warm 

Engine speed (RPM) Terminal B current (A)
1,000 0(1)-70
2,000 0(1)-97
(1) The lower limit must be more than 0 A.
RENDER: 1.0x

NO RELATED

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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.