Why does the camera shutter doesn't open?

@zedit since your 30D starts firing the moment you turn it on but the shutter never opens, it is stuck in a mechanical failure loop. It is repeatedly trying to cycle the mirror and shutter to reset itself, but a broken gear or a jammed blade is preventing it from finishing the cycle. That is what causes the camera to lock up and throw an error.

The exact service manual for the 30D is elusive, but you can use the Canon EOS 40D manual, which references the differences. You will also want to pull up the Canon EOS 30D Parts List to see exactly where the parts are located and how they connect.

First, rule out a stuck switch. Pull the main battery, drip some 90% or higher isopropyl alcohol directly into the edges of the shutter button, and click it rapidly a few dozen times to break up any internal corrosion. Let it dry completely and test it again.

If it still acts up, take the lens off and look inside the mount. If the mirror is stuck halfway or sitting at a weird angle, the mirror charge motor or its small plastic gear has stripped out. If you can see past the mirror directly at the shutter curtains, look for bent, crinkled, or overlapping metal blades. If you see that, the shutter has mechanically destroyed itself. You would have to replace it. Replacing the shutter on a 30D requires completely gutting the camera down to the bare chassis and involves desoldering wires from the mainboard.

While you work on your camera, take lots of pictures :-). Once you are done with it, take those pictures and create a guide for iFixit. That will help the next person who has the same issues with their device. It's easy and fun to create these guides. https://ifixit.com/Guide/new The iFixit community will appreciate this.

Repair is War on Entropy!