FWIW...
back to Canon's standard operating procedure...I call their help line and am filtered thru to tech
service regarding upper end gear. If it's gear related, they run thru a checklist of possible remedies.
Should those remedies not solve the problem, they will not hesitate to email me a prepaid shipping
label for repair. Upon receipt of that gear, an evaluation is carried out and, if out of warranty, an
estimate is emailed which must be paid prior to repair. Their Professional Service, I'm not a member,
provides for free loaner gear while repairs are carried out.
A complaint that always arises is, a direct communication between the client and the actual repair
technician/mechanic cannot take place, it must be filtered thru their Customer Support line...
that is always a real PITA. As I previously said, not all centers are as good as is New Jersey.