How to Change the Alternator on Toyota Cars

by Contributing Writer; Updated June 12, 2017
<p>When replacing the alternator on a Toyota car check the amperage rating on the placard on the alternator. The alternator is available in different amperages, depending on the electrical accessories on your particular car model. When an alternator begins to fail, the diode trio is usually the first to go. The diode trios work in a similar way with one-way valves: The alternator creates alternating current and the diodes allow voltage to pass in one direction, converting the alternating current to direct current. </p>

Under The Hood:

<ul> <li><a href="#how-to-change-the-alternator-on-a-1990-toyota">How to Change the Alternator on a 1990 Toyota</a></li> <li><a href="#how-to-change-the-alternator-on-a-1993-toyota-corolla">How to Change the Alternator on a 1993 Toyota Corolla</a></li> <li><a href="#how-to-change-the-alternator-in-a-toyota">How to Change the Alternator in a Toyota</a></li> <li><a href="#how-to-replace-the-alternator-in-a-toyota-tacoma">How to Replace the Alternator in a Toyota Tacoma</a></li> <li><a href="#how-to-replace-the-alternator-in-a-2003-toyota-corolla">How to Replace the Alternator in a 2003 Toyota Corolla</a></li> <li><a href="#how-to-replace-the-alternator-in-a-toyota-tundra">How to Replace the Alternator in a Toyota Tundra</a></li> <li><a href="#how-to-replace-the-alternator-in-a-toyota-highlander">How to Replace the Alternator in a Toyota Highlander</a></li> <li><a href="#how-to-replace-the-alternator-in-a-toyota-camry">How to Replace the Alternator in a Toyota Camry</a></li> <li><a href="#how-to-replace-the-alternator-in-a-2002-toyota-sienna">How to Replace the Alternator in a 2002 Toyota Sienna</a></li> </ul>

 How to Change the Alternator on a 1990 Toyota

<p>Disconnect the negative terminal from the battery, using a wrench. Loosen the tension on the serpentine belt, using a wrench to move the spring-loaded tensioner away from the belt. Hold the tensioner away from the belt and remove the belt from the alternator pulley.</p>

<p>Remove the plastic electrical plug from the side of the alternator by pulling it out. Remove the large positive wire connected to the "B plus" terminal on the back of the alternator, using a wrench.</p>

<p>Remove the upper and lower bolts that secure the alternator to the bracket, using the appropriate size socket and ratchet.</p>

<p>Lift the alternator out of the engine compartment. Install the new alternator in reverse order of removal. Reconnect the negative terminal on the battery when finished.</p>

Items you will need

  • Set of wrenches

  • 3/8-inch drive ratchet

  • Set of 3/8-inch drive sockets

 How to Change the Alternator on a 1993 Toyota Corolla

Removing the Alternator

<p>Open the hood to access the engine compartment. Disconnect the battery terminals from the battery with a crescent wrench. This will isolate the electrical power.</p>

<p>Locate the alternator on the front of the motor. The alternator will be on the top right along the belt path.</p>

<p>Unscrew the bottom bolt with a socket wrench. Place the bolt to the side.</p>

<p>Loosen the top bolt with the socket wrench. This will loosen the belt enough to take it off the pulley attached to the alternator.</p>

<p>Take the bolt out of the mounting bracket. This will loosen the alternator.</p>

<p>Lift the alternator out from the mounting brackets. Place the pulley on the alternator in a vise.</p>

<p>Loosen the bolt at the top of the pulley with a socket wrench. Remove the alternator and pulley from the vise. Continue loosening the bolt holding the pulley to the alternator.</p>

Installing the Alternator

<p>Take the pulley off the alternator. Bolt the pulley to the new alternator. Place in vise to ensure the pulley is tight on the alternator shaft.</p>

<p>Place the alternator to the brackets in the engine compartment. Place belt on to the pulley.</p>

<p>Start threading the bottom and top bolts. Tighten the bottom bolt with the socket wrench.</p>

<p>Place a pry bar between the alternator and the mounting bracket. Pry the alternator toward the driver side of the car to tighten the belt. Tighten the top alternator bolt. When the belt is tight, there should be no slack on the belt.</p>

<p>Start the car to ensure alternator is operating correctly. Watch the belt and ensure there is no sag as it loops around the pulleys. Turn the car off and let it sit for an hour. Start the car again in an hour to ensure the vehicle cranks up.</p>

Items you will need

  • Crescent wrench

  • Socket wrench

  • Socket set

  • Vise

  • New alternator

  • Pry bar

 How to Change the Alternator in a Toyota

<p>Pop the hood. Unbolt the negative terminal from the battery with the open-end wrench, and then do the same with the positive terminal. Disconnect the connections on the alternator using the open-end wrench as well, and unplug the harness using your hands.</p>

<p>Loosen the pivot bolt at the top of the alternator using an open-end wrench. Then remove the lock nut on the bottom adjusting bolt using a 3/8-inch ratchet and socket. Remove the adjusting bolt using the ratchet and then remove the belt from the alternator. Unbolt the pivot bolt completely, then pull the alternator out of the engine compartment.</p>

<p>Install the replacement alternator in the bracket on the engine, first loosely installing the pivot bolt on the top of the alternator, then installing the adjusting bolt using the 3/8-inch ratchet and socket. Loop the belt around the alternator pulley and then tighten down the adjusting bolt until the belt is tight.</p>

<p>Install the lock bolt on the adjusting bolt using an open-end wrench. Then tighten the pivot bolt using the 3/8-inch ratchet and socket.</p>

<p>Install the wiring to the alternator using an open-end wrench, then reinstall the positive terminal on the battery using an open-end wrench. Follow that by reinstalling the negative terminal. Start the truck and make sure that the alternator charges according to the gauge on the dash.</p>

Items you will need

  • Open-end wrench set

  • 3/8-inch ratchet and socket set

  • Replacement alternator

 How to Replace the Alternator in a Toyota Tacoma

<p>Determine which alternator your Toyota Tacoma will need. You'll want to be sure the new alternator is compatible with your Tacoma's engine. Models made before 2005 may have a 2.4 L, 2.7 L or 3.4 L engine. The current version may have a 2.7 L or 4.0 L engine.</p>

<p>Disconnect the negative battery cable with a socket wrench. Remove the V bank cover and the driver's side radiator support to the frame seal. Detach the radiator fan shroud.</p>

<p>Unplug the harness wiring from the alternator and unfasten the retaining nut on the alternator terminal so you can disconnect the positive battery wire. Remove the drive belt. Take the mounting bolts off of the alternator with a socket wrench and remove the alternator assembly.</p>

<p>Install the new alternator assembly and tighten the mounting bolts to 32 foot pounds with a torque wrench.</p>

<p>Put the drive belt back on and adjust it to the proper tension. Connect the positive battery wire and secure it by fastening the retaining nut on the alternator terminal. Plug the wiring harness into the alternator and attach the radiator fan shroud.</p>

<p>Install the driver's side radiator support to the frame seal and attach the V bank cover. Connect the negative battery cable with a socket wrench.</p>

Items you will need

  • New alternator

  • Socket wrench set

  • Torque wrench

 How to Replace the Alternator in a 2003 Toyota Corolla

<p>Open the hood and loosen the screw that secures the positive battery cable to the battery using the wrench. Pull the cable off the battery to avoid shock.</p>

<p>Connect the adjustable wrench to the metal arm on the tension pulley. Pull the wrench toward the radiator and remove the drive belt from the roller on the tension pulley.</p>

<p>Connect the socket to the ratchet and remove the upper and lower bolts on the side of the alternator. Pull the alternator off the engine. Connect the engine pulley remover to the power drill. Insert the tip on the puller to the nut on the center of the alternator's pulley. Use the power drill to remove the nut and then pull the pulley off the alternator.</p>

<p>Secure the pulley to the new alternator the opposite way that you removed it. Place the new alternator in the engine in the same place as the old alternator. Replace the bolts and tighten the bolts using the ratchet and socket.</p>

<p>Replace the drive belt to the alternator's pulley. Pull the wrench toward the radiator and replace the belt to the tension pulley. Remove the wrench from the tension pulley and close the hood.</p>

Items you will need

  • Adjustable wrench

  • 20 mm socket

  • Ratchet

  • Engine pulley remover

  • Power drill

 How to Replace the Alternator in a Toyota Tundra

<p>Determine which alternator your Toyota Tundra will need. You'll want to be sure the new alternator is compatible with your Tundra's engine. Models built from 2000 to 2004 have a 3.4 L or 4.7 L engine. Models made from 2005 to 2006 offer options for a 4.0 L or 4.7 L engine. Starting in 2007, the Tundra is available with 4.0 L, 4.7 L and 5.7 L engines.</p>

<p>Disconnect the negative battery cable with a socket wrench. Remove the gravel shield if you need to access the alternator from under the car. Remove the electrical connector and unfasten the retaining nut on the alternator terminal with a socket wrench. This will allow you to remove the battery terminal wire.</p>

<p>Unfasten the lock nut, pivot bolt and adjusting bolt on the alternator with a socket wrench. Remove the drive belt and take the alternator off the vehicle.</p>

<p>Install the new alternator assembly. Use a torque wrench to tighten the lock nut to 25 ft. lbs. and the pivot bolt to 38 ft. lbs. Attach the adjusting bolt.</p>

<p>Connect the electrical harness and battery terminal wire to the alternator and fasten the retaining nut to the alternator terminal with a socket wrench. Install the gravel shield if you removed it. Replace the drive belt and restore it to the proper tension. Reconnect the negative battery cable with a socket wrench.</p>

Items you will need

  • New alternator

  • Socket wrench set

  • Torque wrench

 How to Replace the Alternator in a Toyota Highlander

<p>Determine which alternator your Toyota Highlander will need. You'll want to be sure the new alternator is compatible with your Highlander's engine. Models made before 2008 may have a 2.4 L, 3.0 L or 3.3L engine. The current version has a 3.5 L 2GR-FE engine.</p>

<p>Disconnect the negative battery cable with a socket wrench. Remove the electrical connector and the retaining nut on the alternator terminal with a socket wrench. This will allow you to remove the battery terminal wire on the alternator.</p>

<p>Unfasten the pivot bolt and plate washer, and adjust the lock bolt from the alternator with a socket wrench. Remove the drive belt and take the alternator off the vehicle.</p>

<p>Install the new alternator assembly. Replace the drive belt and adjust the tension to 170 to 180 lbs. for a new belt and 95 to 135 lbs. for a used belt. Use a torque wrench to tighten the adjusting lock bolt to 13 foot pounds. Install the plate washer and torque the pivot bolt the 41 foot pounds for a 3.0 L engine and 43 foot pounds for a 3.3 L engine.</p>

<p>Connect the electrical harness and battery terminal wire to the alternator and fasten the retaining nut to the alternator terminal with a socket wrench. Reconnect the negative battery cable with a socket wrench.</p>

Items you will need

  • New alternator

  • Socket wrench set

  • Torque wrench

 How to Replace the Alternator in a Toyota Camry

<p>Determine which alternator your Toyota Camry needs. Be sure the new alternator is compatible with your Camry's engine. Models made from 1982 to 1986 have a 1.8 L or 2.0 L engine. Models built from 1987 to 1993 have a 1.8 L, 2.0 L or 2.5 L engine, and 1994 to 1998 models can be equipped with a 1.8 L, 2.0 L or 2.2 L engine.</p>

<p>Look at late models of the Toyota Camry. Models made from 1997 to 2001 can be equipped with a 2.2 L or 3.0 L engine, and 2002 to 2006 models can have a 2.4 L, 3.0 L or 3.3 L engine. The current generation of the Toyota Camry has been available since 2007 and is available with a 2.4 L or 3.5 L engine.</p>

<p>Disconnect the negative battery cable with a socket wrench. Remove the air intake and engine cover, if needed. Remove the bolts from the accessory drive belt assembly and take it off of its pulley.</p>

<p>Remove the electrical harness from the alternator and unfasten the alternator's terminal nut with a socket wrench so that you can disconnect the terminal wire from the alternator.</p>

<p>Take the pivot and lock bolts off the alternator with a socket wrench. You also need to remove an adjusting bolt if you have a 3.5 L engine. Remove the engine mounting stay, if necessary. Remove the alternator assembly.</p>

<p>Install the new alternator assembly by reversing the removal procedure. Tighten the pivot bolt to 40 foot-lb. and the lock bolt to 14 foot-lb. with a torque wrench. If you have a 3.5 L engine, the adjusting bolt will use a self-adjusting tensioner. Torque the M8 bolt for the drive belt assembly to 15 foot-lb. and the M10 bolt to 38 foot-lb.</p>

Items you will need

  • New alternator

  • Socket wrench set

  • Torque wrench

 How to Replace the Alternator in a 2002 Toyota Sienna

Removing the Alternator

<p>Disconnect the battery's negative cable.</p>

<p>Unplug the electrical connectors to the alternator.</p>

<p>Loosen the alternator pivot bolt--located to the left of the drive belt--with a wrench, then loosen the lock bolt ,which is the lower of the two bolts to the right of the belt. Turn the adjustment bolt--the upper bolt on the right--counterclockwise to loosen the belt and remove the belt.</p>

<p>Remove the pivot and adjustment bolts and then remove the alternator.</p>

Installing the Alternator

<p>Install the replacement alternator on the engine bracket and apply the bolts without tightening them.</p>

<p>Slip the alternator drive belt back onto its pulleys--this is also the belt for the air conditioner compressor--and tighten the pivot, lock and adjustment bolts.</p>

<p>Connect the electrical connectors to the alternator and then reconnect the battery cable.</p>

<p>Push down on the drive belt to test its tension--it needs to deflect by 1/4 inch if there is a distance of 7 to 11 inches between the pulleys and 1/2 inch if the pulley distance is 12 to 16 inches.</p>

Items you will need

  • Wrench

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