Canon EOS-650 repair & common faults
Excellent coverageThe Canon EOS-650 was launched in 1987 as the first camera in Canon's EOS system, introducing a fully electronic EF lens mount with no mechanical aperture linkage between body and lens. It is an autofocus SLR with a built-in motor drive for wind and rewind, so most of its faults trace either to that electronic lens communication or to rubber and foam parts that simply age out on a camera this old.
Autofocus SLR · Electronic EF lens mount · TTL centre-weighted metering · Built-in motor drive · 2 × CR123A batteries
Common Canon EOS-650 faults
Canon EOS-650 won't fire the shutter
On a camera this dependent on battery current for every function, a dead shutter almost always starts with power, so a fresh pair of CR123A cells is worth trying first. If it still won't trip, the fault sits with the electromagnetic release or the shutter's own drive electronics, which is a bench job rather than a battery swap.
Canon EOS-650 LCD screen blank or missing segments
The top-panel LCD reads out through a rubber connector pressed against the display, and on a camera this age that pad has usually hardened or the contacts beneath it have tarnished. Missing digits, faint segments or a screen that only half shows are typical of this, and it's rarely anything to do with the battery itself.
Canon EOS-650 autofocus won't lock
The 650 focuses off a dedicated AF sensor module rather than the lens itself, so hunting or a focus that never confirms usually points to that sensor or its drive coupling. Trying a second EF lens is worth doing first, since a fault confined to one lens is a very different job to one that follows every lens fitted.
Canon EOS-650 aperture blades not stopping down
This was the first Canon body with a fully electronic lens mount, so the aperture is set by a signal through the mount contacts rather than a mechanical lever. Sluggish or absent stop-down usually traces to those contacts or the driver behind them. A wipe of the visible contact pins is a reasonable first check before assuming the worst.
Canon EOS-650 mirror stuck up
A mirror that lifts on firing and won't drop back is a common complaint on cameras of this age, usually down to the foam damper in the mirror box perishing and gumming the mechanism rather than any electronic fault. It tends to get worse with use rather than better, and isn't something to keep firing through.
Canon EOS-650 film advance not winding on
The 650 winds and rewinds on its own built-in motor rather than a thumb lever, so film that won't advance points to that drive train or its gearing rather than anything the user is doing wrong. Worth confirming the back is properly latched first, since the motor won't run at all if it thinks the door is open.
Stuck on your Canon EOS-650?
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Try it now ›Scatto is a reference tool for people who service film cameras. It explains mechanisms and quotes service data, but it cannot see your camera at the bench, so verify anything load-bearing before you act on it.