Advice needed on replacing 0.2mm pitch FFC connector. - Page 1
Forum section: electronics / repair

author: xgabrielx
author_rank: Newbie
timestamp: May 27, 2025, 09:21:35 pm
content: So, my video camera died on me, and it turns out the problem was a flexible PCB deep in the bowels of the camera. I fixed that, but during reassembly, I failed to notice that one of the connectors was the type with the little flap you gotta lift up, and just pushed the end of the strip into it. Obviously, I got a bunch of error codes so I took it all apart to see what was wrong. I noticed some of the pads inside the connector in question had been pushed up and out. I could feel the ends of them poking out from under the flap.So, I bought a new connector, and some low melt paste, and replaced the connector. I used my kitchen oven to bring the whole board up to around 100c, and used a hot air gun underneath the board to solder the connector.But when I test the pins with a dental scraper, I get a few that wiggle. My microscope isn't really good enough to get a good look at what's going on...or rather the built in light isn't. I have to turn iit off and aim a flashlight using helping hands.I'm thinking of just attaching a strip of lead to the connector to give it weight, and simply re-melting the solder that's already on there. Is that worth a try? I have one spare connector in case that fails. But I was under the impression that as soon as the solder melts, the part would be sucked down onto the pads by capillary action or some such.I have a small bare patch of circuit board, right under the connctor, thankfully, so I can shield everything else with kaptan tape and silver mica paper.Is what I'm planning worth a try? Or should I just remove the connector and start over? I can't find a stencil for this connector, and it's pretty hard to get a small enough amount of paste on there to not have bridges. I don't have a fine enough nozzle, and I doubt I'd be able to push solder through it if I did.Failing everything else, I may try applying paste to the pads using a needle, or the point of that dental scraper.

author: thm_w
author_rank: Super Contributor
timestamp: May 27, 2025, 09:54:18 pm
content: Photo will help to understand what you are talking about.Fine tip soldering iron and flux (or solder paste) should normally work.

author: elektryk
author_rank: Regular Contributor
timestamp: May 28, 2025, 11:34:50 am
content: Did you clean residues of low melt solder before soldering new connector?

author: xgabrielx
author_rank: Newbie
timestamp: May 28, 2025, 03:14:37 pm
content: Yeah, I cleaned the pads, and re-soldered. Then just sat the part on top, and melted the solder from beneath. After checking, I noticed that all the pins on one side, are attached to the pads, and most of the pins on the other side, are not. And the pads are smaller on that side, so I guess the solder on them wouldn't have been as high. I assumed the part would be pulled down onto the pads when the solder melted. I guess the pins weren't making contact with the solder on the one side, so they stayed cold, so that side, just kinda floated on the melted solder, instead of being pulled down into it.Something like that, maybe, anyways.I'll post a pic or video when I get a chance to have another crack at it