Which EOS models are vulnerable to broken command or mode dials?
The EOS A2/A2E/5 are the models best known for this problem. The Elan/100 is also susceptible. These film cameras have a design flaw in the main (top deck left) mode dial. The dial has a small central lock button which you must press down before turning the dial. Unfortunately the dial s detent mechanism is held in place with two tiny plastic pins which are easily broken. If they break then the top dial simply freewheels and can t be used for adjusting anything. Quite often the dial becomes stiffer to turn with age, increasing the pressure on the small pins. Some people claim that this breakage problem is user error and that people must always remember to press the lock button down before turning the dial. While pressing the lock button before turning is important it also seems not to be the entire issue, as many users who claim to press the lock button religiously before turning the dial also experience breakage problems. If your camera dial broke under warranty Canon will have replac