Speedo & Tach Problem But Not The Usual.

[bigste]

I have a problem with the above and searched all over but although the problem is mentioned no solution is evident. The problem is all the lighting is fine but on startup the tach & speedo stay at zero. A couple of big bangs on top of the dash usually brings if on, sometimes it comes on by itself after a few miles. I've had it out looking for bad connections and also the cluster was fully renovated a couple of years back. The odemeter and cruise work fine. Any ideas on this would be welcome. There is nothing in the sticky concerning this. It is not always both dials, it can be either or both.

[steve2006]

I seem to remember reading somewhere it was caused by the lubricating oil on the spindles and carefully removing the excess sorted the problem.

[bigste]

I seem to remember reading somewhere it was caused by the lubricating oil on the spindles and carefully removing the excess sorted the problem.

Sounds feasable. Will wait for any more replies before I tend to that.

[CUMan]

Yes, as Steve2006 commented, the tachometer-speedometer problem is caused by a lubricant on the back of the needles. In hot weather, this lubricant liquefies and causes the needles to stick to the stops on which they rest when at zero.

I had this same problem on the 93 LS I formerly owned. I eventually got tired of banging on the dash and took the instrument display out and fixed the problem.

This is not an easy fix. The display has to be completely disassembled to get to the backs of the needles. There are, as I recall, at least four separate components in the display. These are held together with numerous screws and some really strange looking screws that both hold parts together and complete electrical connections. Also, once you have disassembled the display, the area where you need to remove the lubricant is very difficult to get to. The thing you want to accomplish is to get a q-tip or pipe cleaner into the space between the back of the needle and the stop in which it rests at zero. From the front, press the needles against your q-tip and rotate the q-tip. Remove as much of this stuff as you can.

There is an extended thread about this problem on CL. It is in the "stickies" at the top of the LS 400 section. There are pictures showing where to clean the needles.

[Ruud]

An easier fix would be to move to a colder area ;)

[Canopy]

I have exactly the same problem in my 2000 LS400 with 160,000 miles.

Several months ago the tachometer didn't register at startup but then began working perfectly after about 10 miles. Just the other day the speedometer began doing the same thing. So, now I either have one or the other not working, both not working, or both working. Odometer and lights are not affected. Fortunately, once they begin working, they usually contine working unless I shut the car off. Then, sometimes but not always, we go through the drill again.