gregs69rs

I replaced the alternator on my 1999 ES300 with a NAPA unit. The remove and replace went pretty smoothly but when I cranked the car up the alternator is not putting out at all. I am hoping I missed something easy. The likelihood of getting a bad alternator seems very low.

The only issue I had was the plastic clip on the plug that goes into the alternator broke when I was removing it. After 200k miles it was stuck on there pretty good and very brittle. Then, moving all those wires around I worried that they might be brittle and break. At the alternator output post with the car off I get battery voltage so the charge wire is not broken. But when I crank the car I got only battery voltage (11.8) at the alternator post and at the battery.

Did I miss something?

Lexusdk

You may need a new car battery. Your battery is probably not holding charge. If anything have a shop test and charge your battery...

gregs69rs

Its definitely not the battery. The battery is fully charged at 12.5 volts. I am using a multi-meter to test the voltage at the output post on the alternator itself and it is not putting out.

I replaced the alternator because it was putting out low voltage, but it was at least putting out some. 13.5 at the battery with no accessories. Tested that yesterday. Now with the new alternator voltage is 11.8.

I'm thinking the excite wire is not working/is broken but I dont know how to test it.

nsghtbrwry

Does the charging malfunction indicator come on during the cluster bulb test when you turn the key to ON?

gregs69rs

So I pulled the 'new' alternator, had it tested and it was bad. I spoke to a mechanic friend of mine and he said that is common for the rebuilt ones. It was a NAPA which is usually pretty good so i was surprised. Im picking one up from Lexus tomorrow.....

Oro

This is pretty common on rebuilt alternator from major auto parts stores these days. Welcom to China, Inc.

You best bet is to go to a local electical shop and have them rebuild you factory alternator unless you want to pay dealer rebuild prices. The alternative is to rebuild your own, which is not that hard or expensive if you have the capacity and few minor tools.

anhtran

My car 1995 Lexus ES300 not sound when I press door remote. My remote volume is still OK and in max position. Does anyone know where the horn for remote is? Thanks

AmanES300

please don’t spam other threads with off topic posts. You’ve already made a post asking this and were told to check an older thread about the beeper location.

LeX2K

I answered the question here they still went on to ask the same question 2 more times. Trolling or a bot.

Steelfan

I went through this with a starter for my 2006 MDX. Had to get 2 different rebuilds @ Advance before I got a good one. I learned after the first one and had them bench test the replacement rebuild before I left the store.

I still don't know if I would pay the mark-up on the OEM one for this component but, piece of mind does come with a cost.
If it were me, I'd try another rebuild and just have it tested before you leave the store. If they won't do this, go to a different parts store.

Drewsls400

Hello everyone so I've been reading these threads since I got my 91 ls 400 and its helped alot but now I'm having issues with the battery not being charge by the alternator I checked all the wires when I got the car the plug in the back of the alternator was broke and the guy had it just wired in and he had the wires mixed up so when I corrected them alternator works fine it charged the battery for about 2 months then stopped. So I replace the alternator with the remanufactured one from my local alternator repair shop and immediately I noticed that it wasn't charging and battery because two days later I went to go drive the car and the battery was dead now I don't know if there is a relay that I'm missing somewhere or if the ECU is bad or if I have a bad ground so I'm going to go to my buddy's shop the stereo shop and he's going to help me replace all the wiring ground wire to battery ground power wire to the alternator see if that doesn't fix the issue it doesn't is there any ideas of what else it could be any info helps I really appreciate it

HomerJay

Welcome.
As you stated given the history the wiring could be the problem.
What are the voltage readings at idle?
It could also be a weak battery, have it load tested and/or faulty battery terminals.
Separately, it's best to start a new thread and although this is a generic question probably best to post in the LS forum.