is it lack of power or lack steering lock undoing below link might help,, have know cas units due to flat battery and over time to just loose the programming, below is worth a punt it should reset the ecu's and any confusion they might have maybe,
How to reset all ecu's
this procedure is called a power latch
firstly turn on the ignition not engine running,
open bonnet remove battery positive lead and then turn off ignition.
then touch the positive lead to earth,this powers down all ecus and resets erasing intermittent faults in the process.then reconnect the battery lead.
if the vehicle doesnt start straight away leave the ignition on for 2-3 mins as it has gone into anti scanning mode.
IMPORTANT PLEASE READ CAREFULLY
upon starting the vehicle DO NOT TOUCH THE THROTTLE allow vehicle to idle until cooling fans cut in to allow the engine ecu to reset correctly and reprogramme the learning curve,then drive in all gears upto 4,000 rpm accellerating steadily.
as stated this resets all ecus so any electrical faults caused by conflict errors in programming will be erased and fixed.if the fault is still evident there is a problem that will need further diagnosis