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How to Replace Alternator 2002-06 Nissan Altima

Created on: 2013-11-18

Watch this video to learn how to fix battery charging problems. The experts at 1A Auto show how to replace the alternator on your 02-06 Nissan Altima.

  1. step 1 :Disconnecting the Battery
    • Disconnect the negative battery cable with a 10mm socket and ratchet
  2. step 2 :Removing the Engine Cover
    • Remove the four 5mm Allen bolts from the engine cover
    • Remove the engine cover
  3. step 3 :Removing the Alternator
    • Remove the two 10mm bolts from the alternator
    • Disconnect the alternator wiring harness
    • Remove the 12mm bolt from the alternator
    • Attach a 14mm wrench to the serpentine belt tensioner
    • Use the wrench to loosen the belt
    • Pull the serpentine belt off the alternator
    • Release the tensioner
    • Remove the upper of the two 14mm bolts from the alternator
    • Pull off the fuse box cover
    • Remove the 10mm bolt from the fuse box
    • Lift the fuse box and pull it aside
    • Remove the lower of the two 14mm bolts from the alternator
    • Pry out your alternator with a pry bar
  4. step 4 :Installing the New Alternator
    • Put the new alternator into place
    • Start the lower 14mm bolt into the alternator
    • Insert the upper 14mm bolt into the alternator
    • Tighten the lower 14mm bolt
    • Insert the two 10mm bolts into the alternator
    • Put the alternator bracket into place
    • Connect the alternator wiring harness
    • Reconnect the wire from the battery to the alternator and tighten its nut
    • Move the fuse box into place
    • Insert the 10mm bolt into the fuse box
    • Push on the fuse box cover
    • Attach a 14mm wrench to the belt tensioner
    • Loosen the tensioner
    • Pull the belt onto the alternator
    • Release the tensioner
  5. step 5 :Reconnecting the Battery
    • Reconnect the negative battery cable
  6. step 6 :Reinstalling the Engine Cover
    • Put the engine cover into place
    • Insert the four 5mm Allen bolts into the engine cover

Tools needed

  • 5mm Hex Wrench

    14mm Wrench

    12mm Socket

    13mm Socket

    Socket Extensions

    14mm Socket

    Pry Bar

    10mm Socket

    Ratchet

    11mm Socket

Brought to you by 1AAuto.com, your source for quality replacement parts and the best service on the Internet.

Hi, I'm Don from 1A Auto. I hope this how-to video helps you out, and next time you need parts for your vehicle, think of 1AAuto.com. Thanks.

In this video we're going to show you how to replace the alternator on this 2003 Nissan Altima with the 2.5 liter, 4-cylinder engine. This is the same process and part on the Altimas and Centras from 2002 to 2006. The items you'll need for this are a new alternator from 1AAuto.com, 10mm through 14mm sockets and a ratchet with an extension, 5mm Allen bit, 14mm wrench and a pry bar.

Using a 10mm socket and ratchet, you just want to disconnect your negative battery cable.

Now, you want to just remove this engine cover. It's held in by four 5mm Allen bolts. Just go ahead and remove those. On your alternator, you'll see there's one 10mm bolt right here and another 10mm bolt right here. You want to just go ahead and remove those. Disconnect your alternator harness. Just press the tab and pull it free. Under this cap here, you'll see there's a 12mm bolt. Just go ahead and remove that. Now use a 14mm wrench and just place it onto the tensioner right here. Now when you press down on this wrench, it's going to loosen the belt. Pull the belt off the alternator. Try and keep it on the other pulleys and then slowly release the tension on the wrench.

The alternator is secured by two 14mm bolts right here. We'll fast forward as Don removes those. With the lower bolt, you're going to realize it's very long 14mm bolt so we actually have to lift up the fuse box so that we have better access. You want to pull off that cap and then you want to remove this 10mm bolt right here. He did actually need some penetrating oil for that and then you just want to lift it up just enough so you can get that lower bolt out the rest of the way. We just actually push it down with a pry bar and it pulls right out. Now take the pry bar and pry your alternator out.

On the left is the old alternator. On the right is the new one from 1AAuto. You can see they are identical and will mount exactly the same. Now, take your alternator and put it into place and you want to put it into place with that lower bolt. Again just do it from underneath the fuse box. You can leave that bolt a little bit loose. Now replace the upper bolt and once you hand thread that in then tighten both those bolts up. Now you just want to replace these two 10mm bolts along the top here. Make sure that you have that wire in place as you do that. Be sure to put this bracket back in place properly. Reconnect your alternator harness and put the battery wire back on and tighten up that nut. Now you just want to replace that 10mm bolt that secures the fuse box in place and replace the fuse box cover. Take your 14mm wrench, get it down on the belt tensioner, push it down and pull the belt on and you can see here we get it part way up and then we reposition the wrench and get the belt all the way on. Reconnect the negative battery cable. Put the engine cover back into place and replace those four 5mm Allen bolts.

We hope this video helps you out. Brought to you by www.1AAuto.com, your source for quality replacement parts and the best service on the Internet. Please feel free to call us toll-free, 888-844-3393. We're the company that's here for you on the Internet and in person.

2002 - 2006  Nissan  Altima
2002 - 2006  Nissan  Sentra

Shop Products


Alternator

2002-06 Nissan Altima Sentra Alternator TRQ ALA94433

Part Details:

  • Yes
  • 110 A
  • 12 VDC
  • Serpentine
  • 6
  • Yes
  • HITACHI
  • Clockwise (Right)
  • No
  • 58 mm
  • Internal
  • Yes
  • No
  • 32 mm
  • 2.28 in
  • 1.26 in
$164.95
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