What does this mean

[Lac DTS]

>catalyst system low efficency
>secondary air injection (air) system banh #1
>vehicle system voltage below 9.0 volts
>steering sensor rate malfunction

 

[Aaron J Williams]

The most important one of those is voltage below 9 volts. You must first fix the charging system before you can work on any other codes. Low system voltage can cause false sensor codes because the reference voltage is wrong.