First time posting, have hunted through most of the forum related to my problem with no solution yet. I have a 98 gs400 that will not let me turn the stability control off. When I hit the VSC Button nothing happens, no lights on dash indicating the system is off, it does not break traction any easier than without hitting the VSC off button. It does have a CEL but it is for an o2 sensor (P0150). There is no indication of the lights (VSC ABS VSCOFF) on the dash when I crank the car over, as if they do not exist. My speedometer and odometer also do not work (speedo stays at 0, odo doesnt tick up). When swapping into M mode i get no indication on my dash either, and the tiptronic e shift buttons do nothing.(car behaves as if its in auto and will not hold gear). I believe all the issues are related, as I know the abs system can cause the speedo/odo not to work. I have tested/ swapped all speed sensors with no changes. The car is NOT running in a limp mode, everything drives fine as normal, and is not sluggish. I have checked all the wiring harnesses (besides behind the dash directly) as well as any fuses I could find related to the VSC ABS systems. I am the 3rd owner, problem started with the original owner, second owner had the cluster replaced trying to fix the speedo/odo. I have all of the previous owners maintenance records Anybody have any experience with this issue? Any suggestions are appreciated as I am determined to sort it out without a dealership.

 

First thought is the power supply to the cluster fuse in the driver kick panel.

Beyond that I’d say get on tech stream and download the wiring stuff or buy a manual.

 

The complete FSM can be found here: https://charm.li/

 

ill take a look over this weekend while im off work and report back, definitely could be the case.