Please Help I have a Lexus es300, 2001. The car is in very good condition only 10015Ks. Problem is I am on alternator #5 all of these have blown some of the diodes as soon as the car was load tested. First Lexus replaces my battery that did not fix the problem. I had my mechanic look at it and replace the alternator( #1 ) (replaced with Bosh) but still had the same problem. So he replaced the alternator ( #2 )again with a bosh and the same thing. I went out to start the car and it would not start so I used a little booster box heard a noise like tick tick tick for about 5 seconds then there was nothing not even a click when I turned the key. I phoned road service they came out and could not even get it started I had the car towed into Lexus dealership was charged $280 for diagnostic testing, said it was the ECU unit it was going to cost me $1500.00 for a new one or a used one @ $1200.00. I did not do my home work new nothing of getting them fixed or even what they were and just blindly believed what I was told, not a good thing! A little later that day they give me a call telling me I needed brakes done desperately done to 10% front and back. I was really surprised at that, and told them so, I had not even heard them squealing wanting to be safe told them to go ahead and do the them. I didn't have the paper work for the car at home it was in the glove box of the car, after getting the car back I check and another Lexus dealership has serviced the brakes and the fronts were at 75% front and 45% back only 6000 Ks before. I picked up the car paying a hefty bill of over $3000 and two days later again was having the same charging problems but at least it would take a boost, I brought the car into another place ( not Lexus ) I really did not have any faith in them at that time. The new shop did diagnostic testing for $75.00 tells me it is the alternator and replaces it with another Bosh alternator ( #3 ) it did the same thing blew out some of the diodes before leaving the shop, I pay them nothing at that time. They decided maybe the problem was due to the brand and they order me one from Lexus alternator ( #4 ) I pay for this one it costs me over $500. A couple days later the same thing I bring the car back the car back they put in another new Lexus alternator ( #5 ) and add an extra ground cable from the battery to the car body. Few days later the same thing the car is not charging correctly. Repeating the same thing over and over again is my Idea of stupidity. I would definitely appreciate it if some one has any ideas as to what can be causing this electrical problem, or has anyone been plagued by the same. I am bringing in the present alternator to a alternator rebuild shop to see if they can determine as what is causing these alternators to blow. I read on this forum that another person had the same problem, went through 5 alternators finally gave it up and sold the car. At this point I have invested to much money to not give it one more try.