2003 xc90 code p0843

[P1c]

Hi everyone . New to the site, but I'm here often as a guest.

I got a sweet deal on a 2003 xc90 t6. The transmission was rebuilt last year by the previous owner. Car drives like new, engine is great. I have a service light for the trans. Pulled the code and it's p0843. Searched with no luck just general info on the code. Its something like transmission pressure high circuit ... maybe a shift solenoid is not working right?

Can someone point me in the right direction?

Thanks in advance!