topic Re: EOS 700D external trigger overvoltage repair in EOS DSLR & Mirrorless Cameras

EOS 700D external trigger overvoltage repair

Anonymous — Sun, 18 Feb 2024 04:20:30 GMT

Hi, I was attempting to make a DIY external trigger for my EOS 700D and accidentally overvoltaged the 2.5mm trigger port (dumb of me, I know). Now the camera constantly takes photos as soon as it's powered on. I think I shorted something out, as the port is now a dead short when it used to be an open circuit.

I took apart the camera and removed the board with the port on it:

I tested the port with the board unplugged from the camera and it's still a short, which makes me think the problem is within the board itself. However the camera still constantly takes photos when the board is unplugged, so there could be some damage to the main board too.

I'm not totally sure how to proceed now. Ideally I'd like to get the external trigger working again, but I'd also just be happy with the camera not constantly taking photos. Does anyone have any experience with this issue, or have a schematic of the board in question, or something? Or is there a way to disable the external trigger?

Re: EOS 700D external trigger overvoltage repair

p4pictures — Sun, 18 Feb 2024 10:49:21 GMT

I think you may have caused some damage to the main board of your EOS 700D (Rebel T5i). Only way to know for sure will be for Canon service to look at it. But parts for the camera which was launched in 2013, and replaced by the EOS 750D in 2015, might no longer be available. Canon service usually keeps parts for 7 years after a product is discontinued. In all likelihood the cost of the repair will be more than a second hand EOS 700D or even later model in the same line like the EOS 750D (Rebel T6i).

Re: EOS 700D external trigger overvoltage repair

rs-eos — Sun, 18 Feb 2024 13:23:25 GMT

If you end up either getting your camera repaired, or picking up a replacement, note that it would have been cheaper just to get an original part. The EOS T5i (700D) is compatible with both the wired RS-60E3 remote switch and wireless RC-6 switch. They are around $22 and $24 respectively.

See: Compatible Remote Switch (EOS Rebel T5i)

Re: EOS 700D external trigger overvoltage repair

shadowsports — Sun, 18 Feb 2024 14:03:05 GMT

Greetings,

This is one of those situations where you can blindly spend money and time hoping you have fixed something. I wouldn't go down this rabbit hole. The cost to repair will likely exceed the camera's value. It time for a new camera.

Re: EOS 700D external trigger overvoltage repair

Anonymous — Sun, 18 Feb 2024 15:07:58 GMT

Good news! I tested the surface mount components, and found the diode directly below the trigger port was shorted. I unsoldered the diode and the trigger now works perfectly. I assume it was put there as protection for the rest of the circuit if someone stupid like me came along. I could try soldering a new diode in, but as it works without it I think I'll just leave it.

Thanks for all the discouraging advice, but sometimes the solution is a lot simpler than you'd think.

Re: EOS 700D external trigger overvoltage repair

shadowsports — Sun, 18 Feb 2024 17:25:39 GMT

Remember that our advice is based on helping you get the most the most from your gear. Not how to hack it and hope. The success rate on DIY electrical repairs on a camera are under 30%. They often result in more damage during disassembly/reassembly since you might not have the parts needed to complete a repair. As such, our recommendations are not going to include glue, tape or soldering irons. Anything that might leave your camera in a less that 100% functioning state. This includes removing safety features, fusible links, etc. That's up to you. I'd consider yourself very lucky. Hopefully the camera will continue to operate.

Re: EOS 700D external trigger overvoltage repair

zakslm — Sun, 18 Feb 2024 17:43:48 GMT

Stupid? No - not whatsoever!

For those of us that don't know a diode from a transistor let alone having the knowledge and skill to isolate the problem and know the "fix" for it and execute that fix - we are in awe!

Re: EOS 700D external trigger overvoltage repair

Anonymous — Sun, 18 Feb 2024 20:20:24 GMT

Considering you originally suggested I buy a whole new camera, I don't really see the downside to at least trying to fix it first, even if it ends up breaking things (the camera was already broken anyways). But yes, repairing stuff at the component level is not for the inexperienced. However I do have a considerable amount of experience with electronics and proper equipment and was confident that at the very least I wouldn't make it worse.

Re: EOS 700D external trigger overvoltage repair

Anonymous — Sun, 18 Feb 2024 20:34:28 GMT

It's just different skill sets. The people here are more knowledgeable in photography and camera stuff, not so much in electronic repair. I probably would've had more luck asking on an electronics forum. Hopefully if someone has the same problem in the future (however unlikely that may be) they'll find my solution useful.

Re: EOS 700D external trigger overvoltage repair

rs-eos — Sun, 18 Feb 2024 21:36:15 GMT

Note that this is a user forum. So when folks have trouble with gear or need advice, we'll provide user-oriented replies.

Re: EOS 700D external trigger overvoltage repair

mgonidec — Sun, 09 Feb 2025 13:39:26 GMT

Hi! I have a camera on repair from a user that used the snap port. Seems to match your description. Can you confirm which diode you removed? the one below the snap port on the picture? seems a bit burnt actually!

Re: EOS 700D external trigger overvoltage repair

Anonymous — Sun, 09 Feb 2025 15:33:03 GMT

I removed this one, directly below the port.

Re: EOS 700D external trigger overvoltage repair

mgonidec — Sun, 09 Feb 2025 18:09:32 GMT

I can confirm the following:

- I had a 700d that had gone crazy. It would snap a picture right upon powering it up and would not take more when pushhing the trigger button. It would take a shot from the menu button when pushing the trigger. Using the touch screen also worked.

- The user told me he used the snap port, which somehow made me find this lucky thread.

- I tested the diode indicated by LostXOR and it was indeed falty. I removed it!

- Everything seems to be back to normal. I have not tested an extrenal trigger connected with the snap port for now though.

Any clue what the purpose of that diode actually is?

Re: EOS 700D external trigger overvoltage repair

Anonymous — Sun, 09 Feb 2025 19:54:34 GMT

My hypothesis is that it's to protect the port, maybe in case someone plugs in a 2.5mm audio cable and plays a signal through it. Clearly it's not sufficient to protect against everything though (or maybe it's sacrificial, and failing is intentional).