Hello, All of a sudden today the speedometer decides to go above 20 and never come back down, even when the engine is off for a little while. I am not mechanically inclined and I’ve read it could be the speed sensor or cluster panel (rpm, mph, fuel). I don’t have much of anything for tools, but enough to replace a speed sensor based off the YouTube instructions. My dad would be shaking his head right now. Thanks for any help.

 

Does your speedometer work above 20 MPH or does it just stay at 20 MPH?

On these "newer" mostly computer controlled vehicles, it is difficult to tell what the actual cause is through a forum, as the cause can be many things.

You could have a bad speed sensor, bad wiring, bad connections, bad gauge cluster, an electrical problem that causes the computers that run the gauge cluster to be confused, etc.

Is your "check engine" light on?

My best guess as to what is going on is the needle is hanging up at 20 MPH since you said that the needle doesn't go down after you leave the truck off for a while. But that is just a guess.

 

Thanks for the response. The check engine light is not on. The speedometer is still at 20. It will go up, but remains 20 above the actual speed. I don’t have a computer to plug-in, and I hate to bring it to the shop for an inexpensive fix. I suppose that’s the curse of these computerized vehicles.

 

I have the exact same issue with my 2004 gx470 - just started yesterday at FJ Summit in Ouray. Curious what you find. I posed the issue to the Lexus corporate guys that were here, I’ll post up with what they get back to me with.

chris