I have a 1999 GS-300 with 130,000 miles on it. Had lots of issues with the vehicle cranking over recently. Got into my car turned the ignition and click, nothing happened. Tried to crank the engine again and click! Nothing again...... My battery was my 1st thought but, my lights were bright and radio and fan were working right. So I saw a couple postings on the lexus owners club and thought I would tackle this job myself. This problem was intermittent, sometimes the car turned over and sometimes it didn't. Recently it would take me up to 10 minutes for the car to crank over and start, so I had to do something.
I just finished up the job in about 2 hours (start to finish) and thought somebody might read this and make it useful. So here I go to try and tell you how to fix the starter problem and tell you what tools you'll need. Actually after doing the job it was well worth the effort. The problem turned out to be the "Copper Contacts inside the Starter Solenoid" with a total bill of $5.00 (yep I said Five Dollars if you do it yourself).
Before you begin, locate your local Alternator/Starter Rebuilding Shop, you'll need them for the Copper Contacts that are located inside the Starter Solenoid ($5.Dollars) They sold them to me separately.
Tools required: Patience, 10mm., 12mm.,14mm.,15mm,16mm socket, socket wrench, universal swivel socket attachment, (2) Extra Long Socket Extensions 12"inches each, 9/32"nds nut runner or socket.
So here we go: Step by step
1st Things First - you'll need to disconnect your battery to the car both positive and negative leads. Pop your hood. You need a 10 mm. socket and socket wrench to disconnect the battery. (Remember, you'll lose all your settings on your radio, seat memory etc.... but worth it - and if you have any warning light on your dash, like check engine light they'll go off too after you disconnect and reconnect the battery.) The starter and solenoid are located on the driver side of the car engine. They are piggybacked next to each other in one unit.
2nd - you need to disconnect the transmission dip stick to move it out of your way to get the starter out. (You'll need a 12mm. socket with socket wrench) The bolt is located at the top of the dip stick that is attached to the engine. Feel free to pull the dip stick all the way out and put it in a safe place. You don't actually need to take the outside shell of the dip stick out all the way just pull it out about 4 inches and move it to the right or left, it's attached at the bottom by a rubber wire holding clamp. Just move it aside for now.
3rd - Disconnect the lead wires that are going to the starter, there are two - one is a black push connector that you must push the center button in to remove the wire connector as you pull the wire out, and the other is under the rubber black boot that is the power connection that is coming from your battery. Pull back the black rubber boot and expose the 12 mm. nut that must be removed to get the cable off the starter. You'll need a 12mm. socket and wrench to get this nut off. Once you remove the cable put the 12mm. nut back on the starter so it doen't get lost.
4th - Crawl under your vehicle and take your 14 mm. socket, socket wrench and swivel adapter with you with (2) Extra Long 12" inch extentions, you'll need the extra lengths to get the bolts to turn and free your rachet up to swing and loosen the 14mm. bolt heads. Don't take the bolts out all the way, leave them in housing as long as the starter is able to come out. The only reason I say this is because the starter will be easier to re-install once your done fixing it. Now, take your starter out from the bottom, it's a little tight but it will come out.
5th - Put your starter on a work bench or preferably a Vice to hold the starter in place so it won't fall. Locate the (3) 9/32" inch cover nuts and remove them with a 9/32" inch nut runner or socket. Take care not to lose the nuts. Remove the top cover of the solenoid. Once you remove the top cover you'll see the two copper contacts on opposite sides of the solenoid. Remove the center copper solenoid, be careful because at the bottom of the solenoid is a pointed tip with a long 3" spring that actually pushed the started gear out once powered on with your ignition key. Put this center solenoid off to the side with the 3" Spring. Now locate the two copper contacts on opposite sides of the solenoid housing (these are the contacts that need to be replaced.. these are the parts that are causing all your problems with your starter - all for $5 Bucks, notice how black and pitted the copper contacts are). At this point this is where I actually took my whole starter to a Alternator/Starter Rebuildng Shop in a plastic bag with the solenoid cover off and showed them the starter and contacts and they had them in stock. (The 2 Copper Contacts) were tiny copper 90 degree clips with a 1/4 Moon Shape to them, no larger than 1 1/2"inches and no bigger than a quarter. Once I got the Copper Contacts back home the fun started!
I can't believe how little they were and how easy they were going to be replaced for just $5. Five bucks. This was going to save me a ton of money.
Now this is where you'll need to take the (2) nuts off the one side of the solenoid, one nut (12 mm.) is where we originally removed the cable wire from the battery and there is another nut that holds the copper contact into place. I think this is a 15mm. socket (but don't quote me on this one - sorry I forgot what size it was), but remove this nut also, this is the last nut holding the copper contact into place. Once you remove the nut you'll be able to slide the copper contact out, but be careful not to lose the thin washer and small rubber O-Ring attached to the Copper Contact Post. One side of the contact is a Rectangular Copper Square attached to a Copper Post the Copper Contact actually slides over the post for mounting purposes. Take note how the contact is positioned because you'll have to re-install the NEW Copper Contact the same way. You can remove the contact now. Make sure you note what Copper Contact goes where, one is larger than the other. Replace the contact with the same NEW COPPER CONTACT and re-install the same way.
Now on the opposite side, slide back the rubber boot that is covering the other contact post bolt and nuts. Be careful because their is another small washer and "O-Ring" on the other side too. Take care to remove the Copper Contacts the same way and install the other NEW COPPER CONTACT and re-install the same way. Re-assemble the Nuts in the same manner and tighten. Slide the boot cover back over the post and re-assemble putting the center solenoid back inside the housing, re-install the cover of the solenoid. Your starter solenoid is now complete. Re-assemble everything is reverse order and now your done. Hope this helps the Do-It-Yourself Guys.
Any questions, feel free to comment me back. Hope I didn't miss anything....