Ford Repair Questions? Ask a Mechanic for Answers ASAP
there are a few common concerns that can cause a knocking on the steering on this model Focus. First make sure the road springs are still intact, it's possible for a spring to break and still sit correctly on the strut but when you turn the steering the spring jumps causing a knock.
It's very common for the front anti roll bar links to wear on their ball joints, this usually results in a knocking over bumps but worse when turning the steering.
This model originally had a collapsable pedal box in case of a front end impact, the rod between the pedal box and car bulkhead can move against the pedal box this results in a knock when first turning the steering, given the age of your car now though I would expect this to have already been removed to stop this.
Above are common concerns on this model but any steering or suspension joint wear can result in noise so having the steering joints checked is a good option.
I hope this helps, let me know if I can assist further now or when you've spoken to the garage and I'll reply as soon as I'm able to.