Fine soldering help needed: broken laptop keyboard ZIF connector

[jasonbar]

Can somebody here perform a fine soldering task or point me to someone who can?

Long story short:

HP 15T-N200 laptop. Keyboard ZIF connector snapped pretty cleanly off of PCB. Connector is in a few pieces. Connector is (was) a 32-position, 1 mm pitch, horizontal, surface mount, ZIF connector, & an equivalent replacemetn parts is as unattainable as a unicorn.

This Dropbox folder shows hi-res photos of the relevant parts, & I attached some lo-res pics to this post as well: https://www.dropbox.com/sh/57r1n2o4c2r8gbl/AAAIVa1htRQ-Gi6D4VZnD9j8a


So far, local PC repair shops, even ones that advertise motherboard repair, are not enthusiastic about fixing it. I'm confident that this could be repaired reasonably by using an alternate floating connector replacement or even hard-soldering the keyboard flex cable to the motherboard if necessary. It "just" needs somebody who is accustomed to some fine solder work.

Thank you very much,
-Jason

PS--after 1,870 posts over 7.5 years, I finally just noticed the "Message icon" drop-down menu. Wow.

[RandyT]

Ouch...I was hoping this was a cheap unit so I could easily tell you to "junk it", but I see that it is not.  Is this something you bought cheap, hoping to fix it, or a personal mishap?

The issue at hand is that even if you could find a connector, it appears to be one which you couldn't even solder to (i.e. requires reflow).   I'd also be very surprised if it was possible to solder directly to the cable without destroying it.  If it were upside down (and actually had some metal contacts exposed) it could be trimmed back to the contacts, held in place with some hot melt, and each solder point carefully bridged.  But it's not, and I doubt this type of cable would hold up to the heat.  It may not even have any real metal in it to actually solder to.

The prognosis is not good, I'm afraid.  Likely a $200 job for anyone who values their time, if it's even possible.  Probably best to put this in a bartop or cabinet, or use as a desktop system with a USB keyboard.

[jasonbar]

Thanks for the input, Randy. I appreciate it.


I got out my multimeter to check for continuity between the motherboard's rectangular ZIF pads & the neighboring round pads just to their left, in the cases where I could see a clear trace connecting them. I tested a handful & got continuity on only a couple.

Dragging the multimeter probe over the PCB surface, it does feel as if each rectangular pad is a depression, as if the trace did indeed come out.

I added pictures 9-14 to the Dropbox folder: https://www.dropbox.com/sh/57r1n2o4c2r8gbl/AAAIVa1htRQ-Gi6D4VZnD9j8a

These show the bottom of the ZIF connector, & the side-lit shots of the PCB seem to show shadows indicating that the rectangular pads are sub-flush.



I don't necessarily need an exact "stock" replacement. My research has shown that a 1mm pitch, 32-pin, surface mount, horizontal, ZIF connector is as rare as a unicorn.

So, I'm not averse to a skilled workaround where we could solder to the available neighboring pads a fresh connector on flying leads (ribbon cable?) & then plug the keyboard ribbon cable into that connector. It's a modern laptop, so it's slim, but there is a little volume available here, especially if we trim away the steel frame/EMI shield a little, & the keyboard flex cable gives some flexibility.

Or, there are connectors readily available just like the broken one, but in a maximum of 30 positions, so perhaps the cable could be carefully slit lengthwise to feed into a 30-pin connector & a neighboring 2-pin connector, or some other such split (pin 14 on the keyboard ribbon cable appears to be unused & may be a reasonable location to attempt a split).

I'm also not averse to a more "permanent" solution of hard-soldering between the PCB & ribbon cable, eliminating the removable functionality of the keyboard. If there's good strain relief, in the rare case that I'd need to get in to change the hard drive or other component under the keyboard, it can be done. Of course, a coffee spill that breaks the keyboard is another story...


Gotta find a guy who does lots of RGB mods on consoles--they're not afraid to run super fine wire from super fine pads...  :]


Thanks,
-Jason

[MonMotha]

1mm pitch? Trivial to solder.  The 0.5mm ones get a bit tricky but aren't too bad once you get the hang of it.

Unfortunately, you've torn the pads off the PCB.  That'll make it a lot harder to repair.  Still not impossible.

As has been pointed out, the issue is finding the connector.  32 positions is not common.  I can't find any distributors stocking them for qty. 1 purchase.  I can ask my guys at Arrow if they know of anything.

For reference, this is commonly called an "FFC Connector", FCC meaning "Flat Flex Cable".  The style appears to be a rotary backlock.

[jasonbar]

Thank you for your input. Yes, the issue seems to be that this clamp flipped up from the "back" side, opposite of where the flex is inserted, rather than the "front" side, like most of them (AFAIK).

Even a connector w/ > 32 positions might be a candidate to be cut down...?

Thanks,
-Jason

[MonMotha]

You can't really cut them down without destroying the connector, but you may be able to just overhang some excess positions.  You'd have to be careful to properly justify the flex cable when installing it, but I've done this before in a pinch.  Unfortunately, the next size up I know to be common is 40 positions which would be quite a bit bigger.  You can look for maybe 34 or 36, though.

You could also potentially solder small wire (e.g. AWG30) to each position on the flex tail and then tack those down to what's left of the traces on the PCB.  Most (but not all) of the signals fortunately appear to have test points nearby.  The ones without test points would need to either have the soldermask scraped off or a nearby suitable solder point found.  This is a big pain, and it won't be very mechanically rugged, but it would work even if you can't find a suitable connector.  I've done this to break out flex cables to test fixtures in a pinch, before.  It's really time consuming, and it'll be worse in this case since the pads on the PCB that would normally receive the connector have been torn off.

[lilshawn]

EEEEEKKKKK! that is horrible...and yes, those pads are GONE.

luckily it looks lie there is some kind of test connector ajacent to it that looks like it has all the pins from the keyboad there. so at least you have SOMETHING to solder to.

not impossible to do, just a PITA.

get yourself one of those ATA harddrive cables (the fine wire one, not the thick) and peel yourself off a strip of 25 wires (or however many you need) and solder them all on the connector.

then you can follow the traces back and solder the wires one by one onto the diag points.

all is not lost.

you can likely reassemble the connector you have there (after straightening out the pins) remove the ripped off pads from the contacts solder your wires onto it and snap it right back onto the keyboard flatflex.

don't attempt to solder the flat flex, you'll melt it and the conductive material they use for them will not stick to solder anyways.

[jasonbar]

Thanks for all of your valuable input. I've got a couple of paths to resolution at the moment, so I think there's light at the end of the tunnel. :]

Thanks,
-Jason

[MonMotha]

don't attempt to solder the flat flex, you'll melt it and the conductive material they use for them will not stick to solder anyways.

It's very difficult, but I've done it.  You have to be very quick and use as little heat as possible.  Excess flux is pretty much required to get things to stick.  Basically, flux the cable end, tin the wire, put the wire on the contact, and tap with an iron for a fraction of a second.  This is really a last ditch option, though.

[jasonbar]

Thanks for the input, guys. I'm through the tunnel, in the light, without an extra penny spent...but with many hours of my time consumed. Well, I learned a lesson...

Long story short:
1 - Jason contacts HP through HP website explaining his goof & asking for advice, replacement part number, authorized local repair shop, or other options.
2 - HP insists that repair will be free b/c laptop is under warranty.
3 - Jason tell HP clearly that he really appreciates them fixing his laptop for free even though he broke it himself.
4 - HP gives Jason shipping box & FedEx label, & Jason sends of his laptop. (Jason ends up with a spare free box in the ordeal--woohoo!)
5 - A week later, HP e-mails Jason a $350 repair bill.
6 - Jason calls HP, inquiring about the discrepancy. Jason ends up speaking with another HP service department that knows nothing of the first HP department that gave misleading information. Jason understands that he should pay for his own mistake but expresses annoyance that much time was wasted on a wild goose chase path that HP won't honor. Jason could have gotten a faster local repair for that much money. HP rep lacks compassion.
7 - Jason follows up via e-mail to misinformation-disseminating HP e-mail support, expressing frustration. Even if Jason can't get monetary compensation, Jason wants to point out HP's flaw so it can be corrected for future customers.
8 - Jason gets quick e-mail response informing him that his case has been escalated & that somebody will phone Jason shortly. That was 2 weeks ago. No call yet.
9 - A light illuminates over Jason's head, harking back to when he dropped his one-month-old cell phone & cracked the screen. CHASE VISA PURCHASE PROTECTION PROGRAAAAAAAMMMMMMMMMM! Jason contacts Visa, fills out claim paperwork, Visa is fast & helpful & responsive. Visa takes a couple of weeks to process & mail a $350 check to Jason to cover the repair bill.
10 - Jason pays to have HP repair the laptop. (Mobo swap)
11 - Jason gets the laptop. Laptop works.
12 - Jason promptly opens the laptop to repeat the process that got him into this pickle in the first place...except a bit more carefully this time...
13 - When Jason gets to the keyboard FFC ZIF connector, Jason is much more cautious & gentle. Oddly, Jason still can't get that connector to open (though several other similar connectors in the procedure pop open effortlessly).
14 - Jason instead opts to leave keyboard plugged into mobo & does HDD swap by pushing keyboard out of the way rather than removing it. There's enough access room.
15 - Jason installs from disc a fresh, virgin, unmolested MS Windows w/ no HP bloatware.
16 - Jason finds that he needs to track down tons of drivers. What a chore...finally, all those little exclamation yellow triangles in Device Manager have been vanquished! Jason should make a restore disc or something at this time...
17 - Jason's laptop is wicked fast w/ a SSD...and also compared to his 4-year-old ailing laptop...
18 - Jason just received an e-mail from HP Support inviting him to take a survey about Jason's recent support experience. Jason wonders how many characters HP will let him input in the web page form...
19 - Jason closes by saying that Jason usually doesn't talk about Jason in the 3rd person, but sometimes Jason does.

Jason thanks you.
Sincerely,
-Jason

[spoot]

Wait a second........HP is still in business?   

And I'm guessing Jason hasn't done step 16 yet (restore/backup disk).  Jason, you should make Jason do that to help Jason be less annoyed with Jason if sumthing fails.

[jasonbar]

Hey, don't hassle Jason. He's at work. There are only CD-Rs at work. He'll burn a DVD sometime soon when he gets home...

-Jason

[JDFan]

Hey, don't hassle Jason. He's at work. There are only CD-Rs at work. He'll burn a DVD sometime soon when he gets home...

-Jason

Just wait till Jason finds out that "soon" is usually just after failure where that reset disc that Jason was gonna burn would have saved Jason numerous hours of once again tracking down all of those stupid drivers that Jason needs for Jason's Laptop !!

[jasonbar]

Busy week. Just made a recovery disc. Now get off my back, you helpful, patient, respectful guys!!!

-Jason

[greyhound580]

Hi,

I know this post is a little old but did you manage to get this fixed. I have exactly the same issue, same laptop but have acquired some suitable connectors.

regards

[DeLuSioNal29]

As noted above, he sent it in to HP and his credit card recovered his $350 repair fee.

D