Speedometer & Tach have gone out on the car. Tach sometimes works. Odometer & Cruise control still work OK.
Is this is a common problem with the SC400 (w/ 1UZ engine & auto trans)? If so, is it always due to a bad speed sensor on the back of the trans.
Is there a link describing how to test it? Couldn't find it in my search.
I wanted to avoid shelling out ~$165 for new sensor unless I'm certain that's the problem.

Also, does anyone know what lexus models & years use the same VSS as my 92 SC400? I might try looking in junk yard.

 

My 300 just did this the other day so I think it's an SC issue in general. No one has ever really posted a difinitive fix, but if you bang on the top of the console I bet they come right back. DId this to mine and they have worked flawlessly since. If the speed sensor goes out, I think you lose odometer to.

 

It's the motor for the needles that's going out. Just hit the top of the dash like jon said haha. This is a really common problem for the SCs and the only two fixes I have ever heard of are to somehow get a new needle motor which no one has ever followed through on because they are costly, or to just get a new cluster.

 

"Bang on the top of the console"...Seriously?
Is that just to vent my frustration (haha) or is there a loose connection that temporarily gets fixed.

 

When your ****** gets out of line just slap her around. Lol.

 

The needle gets unstuck when you bang on it. I think the motor is siezing up and when you hit the dash it jumpstarts the needle motor if that makes sense.

 

i can sell u 2 motors for 40 bux if u in need

 

Resurrecting this note as I'm finally getting serious on fixing this.
Thanks JDM. I PM'd you.

For rest of CL: Bang the dash method only briefly worked. Now both speedo & tach are dead at zero all the time & 3 of 4 needle lights are out. Anyone know how to fix the speedo & tach motors. I've had the cluster disassembled down to the motors, but couldn't figure out any obvious way to fix them, other than replace. Hearing that dead speedo & tach are a common problem, I'm a bit apprehensive about buying a used one if I'm able to fix the old.
If anyone knows how to fix the tach & speed motors, please reply.

 

^__Bump__ ^
Any know how to repair tach & speedo motors?

 

not here but ill definitely follow this since it is VERY common ..i just replaced mine and was thinking about working on my old one but i need money so im ebaying it..probably should of kept it but all the lights were out on the needles too so id probably cost a pretty penny to fix it all.

 

so my tach just died last night too, it's actually bouncing around from working to dying for a small periodic amounts of time, and then working again, I can't figure out of its the motor that's going out or if its the wiring or a sensor that's gone loose, has anyone else experienced something similar?

 

The motor behind the cluster is going bad, mine does the same but it doesn't bother me at all.

 

you can grab a spare cluster from a similar year SC300 or SC400 (needs to match yours or rpm will be off, speedo cant remember) and transplant the rpm and speedo motors over, they are on the board which holds the needles (duh) and they have the 2 long metal contact points going to the other boards. i dunno if the motor dies or the board sits loose but replacing it is cake and dont forget to calibrate your needles when you put them back in.

 

^^ thanks, will def look into this, I can live w/ the tach going out, but I'm just worried about the speedo

 

how do u calibrate the needles? my rpm need doesn't go past 1k and im looking to fix it by finding another cluster and swapping that board out or try and find just the motor.