Bad USB-C connector on laptop AC adapter - Page 1
Forum section: electronics / repair

author: Peabody
author_rank: Super Contributor
timestamp: February 24, 2023, 04:13:08 pm
content: I have two AC adapters for my Lenovo Thinkpad, which is powered via USB-C. One is in the "datacenter", and works fine in both laptop USB-C ports. The other is in the TV room, and its USB-C connector no longer makes a good connection in either laptop port unless I'm holding my tongue at the right angle.Of course I could just buy a new AC adapter, but I wondered if instead I could buy a 6 ft USB-C extension cable. I would first try to hot-glue the connection between the old connector and new extension while my tongue is at the right angle, hoping that it will stay that way. But if that doesn't work, could I splice the good connector on the extension cable to the existing cord? How many lines am I likely to find in the existing cable? Can I order an extension with the same configuration? Does anyone have experience trying such a splice?

author: donlisms
author_rank: Frequent Contributor
timestamp: February 24, 2023, 07:11:26 pm
content: You're sure it's the adapter connector and not the laptop connector? That could change the game considerably, and would not be surprising. But assuming cable...Hot glue would be pretty far outside the realm of electronic repair, but hey - what do you have to lose by trying?Otherwise, repairing the cable itself would seem pretty much impossible. Cutting both the original and an extension, precision soldering in the middle with great skill and hours or days invested, might work. Maybe. Probably not.I like fixing wherever possible, but this one... probably not.

author: ledtester
author_rank: Super Contributor
timestamp: February 24, 2023, 11:28:31 pm
content: This video shows the teardown of a USB-C charging cable which is permanently attached to a charger:(starts at the 1m mark)Teardown of Samsung 100W USB-C Cable (For New 45W Charger) -- ChargerLABhttps://youtu.be/5ZHF_g88BqI?t=1mThere are only 5 (maybe just 4) conductors.On aliexpress you can find breakouts like this:"1Set Fast Charge Type-C USB 65W 5A Male Connector Welding With 5Pin PCB + Type A Male 6 Pin USB DIY OTG Data Charge DIY KIT"https://www.aliexpress.us/item/3256801151570026.htmlbut I'm exactly sure how they are supposed to be used. It seems that for PD you might only need 4 or 5 conductors.

author: thm_w
author_rank: Super Contributor
timestamp: February 24, 2023, 11:41:24 pm
content: A USB-C power adapter can have as few as three conductors inside. The issue is the C to C extension cable would have a lot more, 10 or more conductors.and if you just splice this charger, which might be 19V? into a plain cable, and then plug that cable into a 5V device, it could blow the ass out of it. Risky.https://www.myfixguide.com/lenovo-thinkpad-65w-pd-adapter-review-teardown/Not sure if the one ledtester linked would make it safe? It only has the one IC.

author: Peabody
author_rank: Super Contributor
timestamp: February 25, 2023, 12:14:20 am
content: Thanks very much for the responses.The adapters I have will supply charging current at four different voltages from 5V to 20V. So I assume some of the data lines have to be connected to permit negotiation between the charger and the laptop.Edit: But looking at the myfixguide page, it looks like that's essentially the same charger as mine, and there are only three lines connected. So apparently just one data line to negotiate PD.Anyway, I think I've waited too long to try a cheap solution this time. So I've ordered a new adapter on Ebay for $20. Once that arrives, then I can take the old connector apart and see if the Aliexpress breakout could be used to repair it. If successful, I would have an extra adapter on hand in case one dies again. But I'm going to research the extension cable further. The time to install one of those is when the adapter is new, so any future connector problems can be solved by just replacing the extension cable, if I can find the right kind.I know everybody loves powering through a type-C port, but I don't. I would rather have a traditional barrel connector, as God obviously intended.