l had the battery replaced about 6 months ago and it worked fine up until this point. l tried to jump it but l beleive the cables were to samll but it did allow for the lights to come on again. Do you think its the starter or something else please help

Sounds like the starter. Happened to my Accord, thought it was the batteries too, you will need to replace the starter before it dies on you and you are stranded somewhere.

First just because the batter is new doese not mean it cant run down.
So, first remove the battery and take it to auto-zone and have it checkec for state of charge. If it is low thy will charge it for you. Also have it tested for load. This test puts a ;oad on the battery to simulate the starting of the car. If it is bad replace the battery.

Now that the battery has been checked out, if it still clicks the replace the starter. It is engageing but not spinning.

1 clean battery cables. 2 check alternator.if battery is good mayb its not charged.3 mayb starter is bad..i would take bat to advance charge it,,, put back.if it starts drive to advance/or other fine store for full free check of battery/alternator/starter.

Charge the battery properly, with a charger, or replace the battery. If u do not have a charger, hook up another car with jumper cables, & let the other car run for at least 5 or 10 minutes while hooked up to ur car. Turn off all accessories on both cars - lights, fans, radio, A/C, seat heaters, everything. For best results, have someone sit in the other car & keep the RPM is at about 1500-2000 rpm while it is hooked up. That will ensure that a lot of juice is getting to the dead car. After 10 minutes or so, try to start u car. If it starts, drive it around for at least 20 minutes or so to charge up ur battery enough to start it the next time.

Be very very sure it is the starter,because it is over a thousand dollars to replace in this car,not counting something else goes wrong in the process.Good luck.

If u have a fully charged battery & u see no corrosion on the battery terminals, then it is a starter. The internal contacts on the starter plunger corrode & do not allow the
starter to engage fully. Not only that LS 400 starters r underneath the intake manifold(Lift the hood & see the
gray thing in the middle- its underneath that). It is a very tedious task to remove this & replace it. Also when replacing this be aware that the age combined with the engine heat causes a lot of hoses, connectors to become brittle & break easily. to summarize be expecting to spend
$$$$

1st step - make sure there is no corrosion around the battery terminals - as it was just replaced, they should be pretty clean

2nd - have the battery checked as well as the battery cables
3rd - have the alternator checked
4th - the starter may be toast

Rule out the easier, cheap fixes first. l have a 1995 LS400 & the starter was the culprit. l had different symptoms though. It would need like 3 cranks of the key to get it turned over. A remanufactured starter is about $125 on Ebay. The bad part is the labor. About 6 hrs of labor & u will need to replace a few gaskets too. Lexus dealers charge about $90-100+ an hour. l would find an independent shop. This is a time consuming repair, but is a known Lexus problem area & is not overly hard to fix.

All that being said, it kinda sounds like it is ur alternator. Again, l would get a remanufactured one off of eBay. Of course this takes time to get shipped to you, & if this is ur only car, u may not be able to let it sit.

Hopefully it is just worn out battery cables.