Mitsubishi codepo 551s

2008?
does car run? and move?
is the Check engine lamp glowing , moving?
yes, and you scanned it and got just ONE DTC?
P0551, (which engine option do you have?)
that code is power steering fail.
check fuses first
use a scan tool to reset the errors
test drive car see if it returns.
same answer any car.
if comes back ,
the sensor is bad,
or its wires fell off.
or you are turning the steering real hard in to a curb and overloaded it.
in the later case, stop that, or we tell you mum.