IMnobody
Newbie
I'd like to see this thread expand, to show other "How To's for Hard Repairs", beyond the current state of, screen & touch pad (module) replacement, that most of us, already can do, or have seen.
This is intended for those that are capable of using a soldering station, and the other tools necessary, to do physical repairs, on the Logic board. It is Other wise intended for educational purpose only, and should not be attempted by the novice user.
(This is not for those with a 40w Ratshack soldering iron & a little nerve. You need a good temperature controlled station, &, a very fine tip.)
Please understand, every one of these I've seen for repair, has been a little bit different as to the actual repairs needed to restore it to operation.
So this is a guide, not a master repair plan for all.
I've come across several units, &, threads where the units, where the USB port, has come loose, or, broken away, from the main logic board.
Not ascribing blame, but, this is generally the result of the phones falling, with the USB cable attached, or, customer impatiens, when installing the cable tip.
The result of this, leaves the unit incapable of charging, or, transferring data, to the phone, though the phone may remain otherwise fully functional.
In most cases the original USB socket can be reusable, other times you'll need to find a suitable replacement. The original drawing number is, "L1037", though the MFG name remains unknown at this time.
But, either way, care must be taken to repair, the unseen damage that results, most of us would miss. The EVO 4G for example, uses a multi-layered circuit board, and part of the surface ground plane is dislodged, when the sock breaks loose. (See Photo)
Picture 1: Is of the typical USB-B socket, with pin out (to show pin functions).
Picture 2: Shows an actual EVO 4G, with the socket broken away from the board, with my notes added.
First, I've no idea what HTC used for solder, to secure parts, to their boards. But, I can tell you, it's very very, harder to work with, and therefore needs to be removed.
The traces need to be reconditioned, before the socket can be re-installing.
I did this by adding 2% silver solder, to the traces, and then removing it again, with Chemwick. Using extreme care, not to over heat the traces, causing them to become lifted from the board (if this happens, your done, there's no further repair possible).
Once the traces and ground points are clean, you need expand the ground points (inward), using an Exacto Knife. Also clean the old solder from the ground pad connections, and add just enough new solder, to clean & bead them up slightly (explained later).
Why do you need to expand the ground points? As you can see in photo 2, a small piece of the ground plane, was ripped away from the board, when the socket broke loose. Being a multi layered board, you can see several small silver spots, remain exposed on the board under where this copper was removed.
These are ground points, which need to be re-established. They are just as important, as the ports connections themselves, for maintain proper operation.
I added a small amount of solder to these points, to get them to bead up, above the board level, with a little smear of solder paste, and luck ( and a good cleaner to remove the solder paste once complete). At the same time, I added solder to "tin" the newly expose expanded copper ground points, I'd earlier made (before removing the solder paste).
I took a small piece of "used" piece of Chemwick, and, trimmed it to size to reach the newly scraped ground area. Added a little more solder, to where it was well saturated.
Then tacked the chemwick, first to the outer edges, then worked inward, to grab the beads.
Next prep the old socket.
You need to remove the old copper trace, from the bottom, &, re-tin that area, so it too, will beads a little. Also, because of the OEM solder, it's a good idea, re-tin the leads as well, again bead a little solder.
Now, your ready to actually reinstall the port. Notice that You have very little room to work with, so, care and good vision are a must. The technique your using is called "Reflow Soldering", you hit each lead quickly (on/off, like a bunny), but, you need to insure you've made a good joint.
The Leads:
You have both the "Pads & Leads", tinned & beaded, with solder. I'd suggest doing the leads first, then come back for the ground points, &, tabs last.
I would work form Pin 5 to 1. Where Pin 1, will be the hardest, because, it's pad is more massive, as it is all Ground plane (more, or, longer heat is needed here). Examine your work after, and, make sure the leads are solid.
The socket base:
I would then clip a small set of Hemostats, to the socket and the bottom of the board. Then heat the socket base up, until the Chemwick (installed earlier) compresses slightly. Do not get the soldering tip so far in, as to allow damage the sockets connections. And, once done "do not remove the Hemostats" until the socket is cooled.
The Tabs:
The Tabs are all that's left to solder, flow the solder evenly, to make a strong joint. Your bound to do better than HTC did here, which allowed the damage to occur. I would also consider flipping the board over, and flowing solder into the plated through hole while the iron and tabs are still hot.
There you have it, reassemble the unit, and, it all went well, you should again be able to charge your battery, and transfer data to your EVO 4G.
Like I've said, I'd like to see more detailed extreme repairs, appear following this post. not so much comments.
If I could find the actual parts, or, part number for reference. I'd also be willing to show how to replace the damaged LCD & Digitizer sockets. I have 3 units currently in this condition, where module replacement went badly.
IMnobody
This is intended for those that are capable of using a soldering station, and the other tools necessary, to do physical repairs, on the Logic board. It is Other wise intended for educational purpose only, and should not be attempted by the novice user.
(This is not for those with a 40w Ratshack soldering iron & a little nerve. You need a good temperature controlled station, &, a very fine tip.)
Please understand, every one of these I've seen for repair, has been a little bit different as to the actual repairs needed to restore it to operation.
So this is a guide, not a master repair plan for all.
[SIZE=+2] USB Repair[/SIZE]
I've come across several units, &, threads where the units, where the USB port, has come loose, or, broken away, from the main logic board.
Not ascribing blame, but, this is generally the result of the phones falling, with the USB cable attached, or, customer impatiens, when installing the cable tip.
The result of this, leaves the unit incapable of charging, or, transferring data, to the phone, though the phone may remain otherwise fully functional.
In most cases the original USB socket can be reusable, other times you'll need to find a suitable replacement. The original drawing number is, "L1037", though the MFG name remains unknown at this time.
But, either way, care must be taken to repair, the unseen damage that results, most of us would miss. The EVO 4G for example, uses a multi-layered circuit board, and part of the surface ground plane is dislodged, when the sock breaks loose. (See Photo)
Picture 1: Is of the typical USB-B socket, with pin out (to show pin functions).
Picture 2: Shows an actual EVO 4G, with the socket broken away from the board, with my notes added.
First, I've no idea what HTC used for solder, to secure parts, to their boards. But, I can tell you, it's very very, harder to work with, and therefore needs to be removed.
The traces need to be reconditioned, before the socket can be re-installing.
I did this by adding 2% silver solder, to the traces, and then removing it again, with Chemwick. Using extreme care, not to over heat the traces, causing them to become lifted from the board (if this happens, your done, there's no further repair possible).
Once the traces and ground points are clean, you need expand the ground points (inward), using an Exacto Knife. Also clean the old solder from the ground pad connections, and add just enough new solder, to clean & bead them up slightly (explained later).
Why do you need to expand the ground points? As you can see in photo 2, a small piece of the ground plane, was ripped away from the board, when the socket broke loose. Being a multi layered board, you can see several small silver spots, remain exposed on the board under where this copper was removed.
These are ground points, which need to be re-established. They are just as important, as the ports connections themselves, for maintain proper operation.
I added a small amount of solder to these points, to get them to bead up, above the board level, with a little smear of solder paste, and luck ( and a good cleaner to remove the solder paste once complete). At the same time, I added solder to "tin" the newly expose expanded copper ground points, I'd earlier made (before removing the solder paste).
I took a small piece of "used" piece of Chemwick, and, trimmed it to size to reach the newly scraped ground area. Added a little more solder, to where it was well saturated.
Then tacked the chemwick, first to the outer edges, then worked inward, to grab the beads.
Next prep the old socket.
You need to remove the old copper trace, from the bottom, &, re-tin that area, so it too, will beads a little. Also, because of the OEM solder, it's a good idea, re-tin the leads as well, again bead a little solder.
Now, your ready to actually reinstall the port. Notice that You have very little room to work with, so, care and good vision are a must. The technique your using is called "Reflow Soldering", you hit each lead quickly (on/off, like a bunny), but, you need to insure you've made a good joint.
The Leads:
You have both the "Pads & Leads", tinned & beaded, with solder. I'd suggest doing the leads first, then come back for the ground points, &, tabs last.
I would work form Pin 5 to 1. Where Pin 1, will be the hardest, because, it's pad is more massive, as it is all Ground plane (more, or, longer heat is needed here). Examine your work after, and, make sure the leads are solid.
The socket base:
I would then clip a small set of Hemostats, to the socket and the bottom of the board. Then heat the socket base up, until the Chemwick (installed earlier) compresses slightly. Do not get the soldering tip so far in, as to allow damage the sockets connections. And, once done "do not remove the Hemostats" until the socket is cooled.
The Tabs:
The Tabs are all that's left to solder, flow the solder evenly, to make a strong joint. Your bound to do better than HTC did here, which allowed the damage to occur. I would also consider flipping the board over, and flowing solder into the plated through hole while the iron and tabs are still hot.
There you have it, reassemble the unit, and, it all went well, you should again be able to charge your battery, and transfer data to your EVO 4G.
Like I've said, I'd like to see more detailed extreme repairs, appear following this post. not so much comments.
If I could find the actual parts, or, part number for reference. I'd also be willing to show how to replace the damaged LCD & Digitizer sockets. I have 3 units currently in this condition, where module replacement went badly.
IMnobody
