The CI and CA error codes indicate that current (amp draw) limits for the drive motor were exceeded. Since you indicate that these codes were displayed even though the washer is not overloaded, it is likely that you have a problem with the motor, motor controller or the universal joint. An item stuck underneath the nutate plate or between the spin basket and the outer tube of the washer could also cause this problem.
If you want to diagnose and repair this problem yourself, I recommend that you
unplug the washer
and open the console to check the continuity of the motor windings first. The first image below shows the procedure for opening the console of the washer. With the washer unplugged, you can check the resistance through the drive motor windings from the motor control board. You should measure around 6 ohms through the red and yellow wires on the P6 connector of the motor control board. You should measure between 2 and 5 ohms between the red and the white/black wires. You should also measure between 2 and 5 ohms between the yellow and white/black wires. If you find a shorted (measures near zero ohms) or open winding (measures infinite resistance or Ol - open load) in the motor then the resistance will need to be checked directly at the motor. If a winding is bad in the motor then it will need to be replaced.
NOTE: You should only attempt to diagnose and repair this problem yourself if you are completely confident in your technical ability to safely access and test components in the washer. Follow electrical safety guidelines.
Unplug the washer
before accessing internal components. Internal metal edges in the washer can be sharp. Protective gloves are recommended.
If the resistance through the drive motor windings is okay then I recommend that you pull out the wash (nutate) plate (with the washer still unplugged) and check for an item underneath it as shown in the second image below.
These tips may help you determine the cause of your motor problems in the washer. If not, then you will likely need to have a service technician diagnose and repair the washer. Here is a link for the Sears Service website:
Sears Home Services