"I have the right combination of skills and experience for this job. I also bring the additional quality of strong analytical and problem solving ability as shown by my introduction of a more efficient work"
"My commitment to excellent work standards will add value to the team."
As a project manager, overall understanding of how to make a successful project is what's important. Knowing how to code will depend on the size of the project and the team of developers. It is true that developers will always trust a project manager who knows the intricacies of coding, but, it's just as important be provided all the necessary feedback and detail in terms of what the project entails. You could know how to code very well, but not be able to organise the work or delegate properly. On the other hand, you may also be very organised but have no idea how much time work takes. I don't think that it's essential to know how to code, but, if you are a good project manager and know how to lead the team and supervise the project, knowing how to code is also a big plus definitely.