Speedometer works intermttently
 

The speedometer on my 94 LS400 works intmittently. Everything else works fine(tach, cruise, lights, ect) but the speedometer quits every once in a while anyone have any ideas what to check?? I am new to this forum and have never been on one before, so maybe I'm doing this right.

My guess is a dying #1 or #2 speed sensor. Trying checking for any codes: http://www.lexls.com/tutorials/intro/codereading.html

My cause was a leaking power steering pump that was wreaking havoc on the alternator that was sitting right below it...

My power steering pump leaked for a long time.
 

Before I was able to repair it and now that you say this I believe it may be tied into that, because that is when the problem started. What is the problem with the alternator and how is this tied in with the speedometer?? Do I need to replace it or is there another remedy? Thanks for the advice please reply asap. Tom:egads::egads:

LexLS
 

LexLS: Can't help but noticed your name. Your web site has help so many people across USA (and probably around the world). Any chance you will buy another Lexus soon? Hope you will. Best wishes.

The power steering fluid leaks into the windings of the alternator and slowly the alternator dies, as it does it won't be putting out the correct voltage to start the gauge motors..and eventually other motors like the blower fan. You need to replace the power steering pump and alternator if this is the case...you *may* be able to clean the alternator...and replace the correct o-rings in the pump. I waited to long and my alternator died completely...

Could be a faulty cluster also. Even though everything else seems to be fine.
Let us know what you find.

the legend returns!

:hail:

I Repaired The Pump Months Ago
 

This makes perfect sense to me. I repaired the pump months ago. I believe it was the vacuum hose fiiting leaking and I pluged it and stopped the leak. I am doing a complete timing belt replacement, along with cam sensors, plugs, plug wires, waterpump and all that goes with this. The alternator is just an oily mess, greasy on the outside so, I bet your right, I'm not getting the correct voltage out of it. I tried to get the alternator loose and only was able to get the main power cable off of it. I couldn't get the plug with the little wires to come out. So I have to get it unplugged some way and see if there is anyway to clean it up. If you have any knowlege of how it comes unplugged I sure would use the advice. I am going back together with the front end and I'm going to need to either replace of repair soon so I can complete this. I started this two weeks ago today and then had to wait on some parts that were shorted in the order. Now I have them and it's going together nicely but while I'm here I need to do this. Thanks, Tom :eek2:

It's a PAIN to remove when it's covered in fluid!

I had to loosen the power steering pressure line (I think) that is attached around the oil pan, then unbolt the alternator, pull it off the studs, then twist the alternator to get better access to the wiring. It's tough to hold onto and see what you are doing when it's covered in fluid.

I'd be surprised the vacuum hose (or whatever you plugged) was the only leak on the pump. These pumps are notorious for leaking when the seals/o-rings get old. I'd probably rebuild it and/or get another one while you are at it.

As far as cleaning the alternator...that was just a suggestion. I have no knowledge of anyone being successful in that endeavor.

Going To Try & Clean
 

I'm going to give it a try and see if it does the trick. I'll let you know how it turns out. If not I'll replace it. Thanks for the input.

Good luck.

Try and clean the pump as well, if you don't rebuild it..that way you'll be able to tell down the road if it's still leaking.

No Leak
 

No, it's not leaking. I repaired it last year or the end of 2010 and there hasn't been anymore power steering oil since. This is just oil on the alternator that has been there since then.:)

I actually took my alternator out a few years ago, because I was SURE it was causing a low battery voltage problem, after making dozens of measurements. Guess what? It turned out to be an intermittent bad cell in my 1-year old battery. Boy, was I mad at myself, because that's a lot of work. With over 100k on the car, I figured I should at least replace the brushes while I had it out, so I took it apart. Brushes were only 30% worn, and they are hard to find, so I just put them back in. The reason I mention all this is because I see several posts about how leaking ATF has ruined so many alternators. The Denso alternator is extremely well made, and it is much more likely that the fluid has only contaminated the brushes or slip rings. I would bet that you can simply clean any gunk from the brushes and the inside, maybe polish the slip rings with very fine sandpaper, put it all back together and get it tested for free at one of the auto parts places. AFAIK, there is nothing else in the alternator that would be impacted by any auto fluid; windings and diode packs should not be phased by it (unless it gets so clogged with debris that it overheats). It's certainly worth a shot.

Steve