04-23-2017 10:09 PM
Solved! Go to Solution.
04-24-2017 05:48 AM
About the battery door. You have a micro switch there that will need a closed battery door or an attached battery grip. Else the camera will not power up.
04-24-2017 06:32 AM
The on-camera shutter button should work even with the grip attached.
It sounds as though you may have a faulty shutter button, it is quite common for these to get dirty contacts and become a bit erratic on all conon DSLRs not just the 40D. I would suggest that you try repeatedly pressing it while the camera is turned off in the hope that it might clear.
There have been some DIY fixes posted on the internet by squirting cleaner fluid into the battery compartment but I would be reluctant to try this because you could damage the top LCD.
If you bought this camera from a dealer then perhaps they might fix the problem for you otherwise you may have to pay to get the shutter button replaced.
04-24-2017 11:07 AM
Most Canon battery grips have a spot where it hides the battery door. The long post that inserts into the battery bay may actually have your door hiding on the side of it (it would be easy to miss if you didn't realize it was there.)
04-25-2017 05:05 AM - edited 04-25-2017 05:07 AM
A quick search at Google tells me it's not an unfamiliar problem with the 40D. Search for 40d shutter button or Contact cleaning the shutter button in Canon 40D. Also Fix shutter release button not working Canon 30D 40D 50D.
The best is probably to open the camera up and clean the contact. The easiest is probably to put alcohol at the battery place holding the camera upside down. Don't forget to clean the battery compartment before. To get a 40D reparied costs probably more than the camera is worth.
04-25-2017 05:49 AM
The shutter button has 2 seperate sets of contacts, the first one turns on the metering and the focusing, the second one actuates the shutter so it is possible that it is only the second contact that is causing the problem.
The fact that it is firing the flash is a bit misleading because the intial flash that you see is probably the pre-flash that is triggered indirectly by the metering contact this is normally followed by the main flash that is triggered by the shutter mechanism. Normally this happens in quick succession and you do don't notice it flash twice. I wouls suggest that you are only getting the pre-flash because the shutter mechanism isn't moving.