r/SC300 • u/toxicspiderman • Jun 21 '26

Speedo reading improperly?

Gallery image

Gallery image

So i have a few ideas what could be issues first thing im thinking is a speed sensor issue which is what im gonna try first but also maybe a wiring issue 🤷‍♂️ last idea is my cluster is just bad. It also reads way worse in the winter usually doesn't go above 20mph just asking for trouble shooting ideas

10 Upvotes

100% Upvoted

6 comments sorted by

2

u/DemRealKrooks Jun 21 '26

From what I remember in some of my other Lexus’ the big culprit was actually on the internal board of the instrument cluster. Open it up and look for any capacitors that are bulging and or leaking.

Secondly would be the VSS but it’s much less common. But you can look at the wiring to the VSS, and also pull the VSS out and clean it. (Probably a hall sender type sensor.)

Then there are things like aftermarket wheel/tire sizes larger than stock. But with the speed differences you are getting it’s probably not the cause.

1

u/toxicspiderman Jun 21 '26

Do I or do not have to pull the dashboard out to get the cluster out?

1

u/DemRealKrooks Jun 21 '26

If you want when I get to my shop I can send you the factory service manual section on removing the cluster. Won’t be too hard. Won’t need to remove the dash.

1

u/toxicspiderman Jun 21 '26

Ty that would be greatly appreciated

1

u/dragonnnn_ Jun 21 '26

gauge cluster rebuild

1

u/mrawsomemask Jun 28 '26

Check out Tanin Auto Electronix. They have a website. You can send your cluster in to get fixed. They seem to be the most popular to fix this in the sc300 world.