I spent a few hours troubleshooting my remote fiber-cellphone hardware today. My memory is so poor it's a relearning project, though fortunately with pretty good documentation. The fiber-phone was a 2006 project, all hand soldered, no PCB, with a Picaxe M18 controller. Ended up being one of the few Molex insulation displacement connectors I have left on that...on the 12v power to the solenoid that pushes the button to turn on the cell phone.
I never use Molex IDC connectors anymore, for good cause. The contact to the wire is just not reliable over time.
Not much fun working in the cell phone dog house when you're having a bout of Graves and your heart is going 100 BPM and your hands are shaking.