My steering is light when I start off

This issue is most likely a power steering pump that is failing. When the fluid is thick the pump is able to build pressure however, as soon as it starts to get hot, the pump loses the ability to build pressure because the fluid is thinner.

Here is a guide that will help with this:

https://www.2carpros.com/articles/power-steering-problems

I would suggest replacing the pump and then retest the system. Here is a guide that will help with this.

https://www.2carpros.com/articles/how-to-replace-a-power-steering-pump

Unfortunately, we don't have a manual that will give the specifics, but this guide should help enough to get the job done.

Please run through this and let us know what questions you have. Thanks