I have a 95 Lexus es300. My alternator went bad no big deal right! So I changed it out everything was fine but I notice major power drain after a week. the diode had went bad. So luck of the draw I figured new alternator went bad so switched it out three days later the new alternator is doing the exact same thing bad diode. What the hell

Make sure the battery is good. U can charge it and disconnect it from car overnight and see if it works the next day. If it is still fine then the car has a drain. If no good, then the battery is bogus and cannot hold a charge.

U have something in wiring that is draining the battery after shutdown. Need an ammeter. Hook it up to the battery and wait about a half hour. Then notice draw on meter. Start removing fuses until you locate the line that is responsible for the draw. Then check out each and every item on that trunk line.

get your car fix right now
TOYOTA LEXUS ES300 SERVICE REPAIR MANUAL 1993 1994 1995 1996 1997 DOWNLOAD

Diodes fail from excessive current flow for the diode. For this to happen there has to be a short in the diode circuit . Take the vehicle to an accredited auto electrician for an evaluation of the circuit where the failure is occurring

You may think that there is a connection problem of the headlights to chassis ground,check the wire connetions and lightning relays

Usually that fuse powers the alternator and the fuse box.
It would have to be a big short to ground to blow that fuse.
Its possible the main wire to the alternator is touching a metal spot, or the alternator is shorting out inside when it is running.
What is draining the battery may be something else, or the battery could be discharging after the fuse blows if the alternator is not charging it.

The 2003 Lexus ES300 has the most common hook-end wiper arms. If you purchase the replacement blades first, there will be additional instructions/illustrations on the replacement packages. Locate and press the tab or button where the wiper blade is inserted into the hook of the wiper arm and pull wiper blade out of hook. You may have to rotate and flex the blade to make enough clearance for the hook to pass through.

2003 Lexus ES300 Wiper Blade Videos (hook-end arm)

2003 Lexus ES300 Wiper Blade Size Options w/Correct Lengths & Attachments

could be your alenater, your check you cable wires for good connection.

IM SUGGEST YOU TO CHANGE THE CAR, THE PROBLEMS BEGINING SOON

Have the charging system checked out. The battery,alternator,and starter.Also if all of this checks out you may have a battery draw(something draining the battery). If you use your car every day it will never show up.

The future of the reform of the radio signal