How To Replace A Mazda Alternator

Even when you properly maintain your vehicle, charging system failures can happen suddenly at higher mileage. That results in unexpected repairs. Thankfully, a DIY alternator replacement can be less difficult than you think, and may save you hundreds of dollars.

Before You Begin

mazda belts

Before replacing your Mazda's alternator, ensure that you’ve had a charging system test performed to determine that the alternator is bad. It's important to confirm that the alternator has failed because it's not the only cause of charging system issues. There are a variety of parts that could fail that leads to alternator or battery malfunction, such as:

This diagnostic guide will help you determine whether the alternator is the issue or if it's something else. If you've determined that the alternator has failed, read on to find out how to replace it at home.

What You Will Need

You can find and purchase the correct OEM alternator for your Mazda vehicle here.

Once you’ve purchased your new alternator and and you’re ready to install it, here are some basic tools that you’ll need to do the job:

  • A metric 3/8” drive ratchet and socket set with extensions (8mm through 19mm size sockets recommended for most Mazda repairs)
  • A set of metric wrenches (8mm through 19mm size wrenches recommended for most Mazda repairs)
  • A serpentine belt tool (which can be rented at some auto parts stores)

Replacement Instructions

Mazda alternator

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While the procedure may vary between Mazda models, follow these basic steps to replace your alternator:

  1. Loosen and disconnect the negative battery cable.
  2. Identify the location of the alternator.
  3. Remove any plastic engine cover that may obstruct access.
  4. Remove any plastic air deflector under the vehicle that may obstruct access.
  5. Release the belt tensioner and then remove the serpentine belt. (It's a good idea to take a photo first for belt routing.)
  6. Disconnect the electrical connector from the alternator.
  7. Loosen and disconnect the battery cable from the alternator.
  8. Remove any bolts fastening support brackets to the alternator.
  9. Remove any bolts fastening the alternator to the engine block.
  10. Carefully wiggle the alternator loose from its mounting location.

To install your new alternator, follow the previous steps in the reverse order.

Returning Your Old Alternator

Your new alternator includes a core deposit charge.  This means you must return the old alternator (core) to receive a refund for the deposit. Be sure to save your receipt or order number and the box from your new alternator.

Verifying Your New Alternator is Working Properly

Once your new alternator is installed, have a charging system test performed. It's to verify your repairs and to determine the health of the battery when it is charging properly. If you’ve determined the battery needs replacement, you can shop for one here.