90 Ls 400, Speedometer/odometer Not Working

[Aggievet03]

I just picked up a 1990 LS 400 in pretty good shape, but the speedometer is dead. The needle is buried way below zero and never moves. The primary mechanical odometer also does not move. Oddly, however, the two digital trip odometers work just fine and cruise control works perfectly.

Is this likely an instrument cluster issue or a speed sensor? something else?

What's the simplest way to diagnose this?

Thanks in advance for any insight.

-Matt

[Exhaustgases]

I think its a small gear that wears out, since it is a little motor that runs it. The sensor must be okay since the trip odo works ok.

Edited January 13, 2016 by Exhaustgases
add the S to sensor

[Aggievet03]

Are you referring to a small gear in the instrument cluster that drives both the speedo and odo?

[1990LS400]

The mechanical odometers in the 90-92 LS400 had a high failure rate. The one in the 1990 LS400 I drove from new until 2003 failed in the late 90's at around 120,000 miles if I remember correctly - I think I still have it in a box in the garage.

The speedometers and tachometers are also known to fail. It could be the speed sensor but I doubt it. I would ship the instrument cluster to http://www.taninauto.com/ and have them look at it. You might ask if they can repair the mechanical odometer since new replacements have not been available for many years.

[catdogdoc]

My 91 LS400 came with no lights on the instrument cluster working. I pulled it and sent it to be rebuilt. Now all the lights work but the speedometer, all odometers don't work. Also, my 'O/D off' light is blinking. I have read this may be the vehicle speed sensor on the transmission. Is the best way to determine this just to take it to dealer for diagnosis?

[Exhaustgases]

On Sunday, January 10, 2016 at 4:47 PM, catdogdoc said:

My 91 LS400 came with no lights on the instrument cluster working. I pulled it and sent it to be rebuilt. Now all the lights work but the speedometer, all odometers don't work. Also, my 'O/D off' light is blinking. I have read this may be the vehicle speed sensor on the transmission. Is the best way to determine this just to take it to dealer for diagnosis?

So did you send it to TANIN ? And when you send it you tell them what doesn't work. As it can not be fixed if they don't know its broken.  Who did you send it to?

[catdogdoc]

I sent it here:

Mikado Technology Company in Gilroy, California 95020

The number one facility re-manufacturing Lexus Toyota Scion Clusters/Speedometers.

Yes, I told them they weren't working. He said it ran fine on the bench test. He said it may be the electrical connectors.

[sha4000]

Seems like that company did not test it thoroughly although it could very well be the connectors. Did they give you an option to send it back?

[catdogdoc]

We are still in communication. It's warranted for 1 year, so I think he will honor that. The speed sensor may be worth looking into from what I have read in other posts, since the speedometer, odometer, and O/D off light are all affected. I tried looking for that today but didn't have the car jacked-up. I may take it to a mechanic I know and have him put it up on a rack. The sensor isn't much if I can replace it myself. I'm trying to sell this car, so I don't want to put much $ into it, but hard to sell with current issues. Thanks for your advice.