UK Car Repair Questions? Ask a Mechanic for Answers ASAP
I am sorry that you have not been helped yet. I just came online and saw your question
Either the volume control from the steering wheel button on the replacement steering wheel is not working, which will affect the radio volume, or they pinched a wire on the installation process.
If you plan on pulling the steering wheel to inspect it, I just need the last 8 of the vin to pull up and upload the procedure for you