How to Change the Alternator in a 1994 Lexus GS300

In the early 1980s, Toyota had entrenched itself in the U.S. marketplace with its simple, economical and reliable vehicles. Toyota frontman Eiji Toyoda saw an opportunity to profit on the American buyers' love for luxury cars such as BMW and Mercedes. Toyota, with its reputation, wouldnt stand a chance against top-end cars of the era, so Toyota Motor Company released the luxurious Lexus lineup in 1989. In 1993, the GS300, Lexus first sports sedan, hit showrooms. Replacing the alternator on a 1994 GS300 is much simpler than the car's high-tech appearance might lead you to believe.

Instructions

1

Loosen the pinch bolt on the negative battery cable end with a combination wrench and pull the negative battery cable from the battery. Wait at least 90 seconds before starting the removal process of the alternator.

2

Raise the vehicle with a floor jack and slide jack stands under the GS300s frame rails. Slowly lower the Lexus onto the jack stands.

3

Crawl beneath the GS300 and remove the bolts securing the engine splash guard, using a ratchet and socket. Remove the splash guard and set it aside.

4

Look on the front of the engine and find the serpentine belt tensioner near the center of the engine block. Place a ratchet and socket on the bolt in the center of the pulley and rotate the pulley clockwise to relieve the tension from the serpentine belt. Pull the serpentine belt off the alternator only, leaving it attached to the remaining pulleys. Slowly release the tensioner pulley.

5

Press and hold the unlocking button on the alternators wiring harness, then unplug the harness from the rear of the alternator. Pull the rubber cover back from the end of the power wire and remove the power wire-retaining nut with a ratchet and socket. Pull the power wire from the alternator.

6

Remove the alternator retaining bolt; notice that bolt also secures the automatic transmission line routing bracket. Pull the transmission hose routing bracket from the alternator.

7

Remove the nut securing the alternator using a ratchet and socket, and pull the alternator downward from the engine compartment.

8

Guide the new alternator into the engine compartment and onto its mounting stud from the underside of the vehicle. Hand-thread the alternator retaining nut, then align the bolt hole on the alternator with that in the alternator bracket. Set the transmission line bracket in place on the alternator and hand-thread the alternator bolt.

9

Tighten the nut and bolt to 27 foot-pounds with a torque wrench and socket. Guide the power wire onto its stud on the new alternator and hand-thread the retaining nut. Tighten the retaining nut until snug using a ratchet and socket. Plug the wiring harness into the receptacle on the new alternator.

10

Rotate the tensioner pulley counterclockwise with a ratchet and socket and guide the serpentine belt over the alternator pulley. Slowly release the tensioner pulley.

11

Set the splash guard back under the engine and hand-thread its retaining bolts. Tighten the splash guard bolts with a ratchet and socket.

12

Raise the GS300 off the jack stands with a floor jack and remove the jack stands. Slowly lower the Lexus to the ground. Press the negative battery cables end back onto the batterys negative post and tighten the pinch bolt with a combination wrench.