|
|
Post by wvengineer on Mar 17, 2016 23:13:12 GMT
I have a Samsung Galaxy S4 as by personal phone. It has had very few issues until the last few weeks. It seams to randomly loose connection with the SIM card. When it does so, it stops everything and you have to reboot and hope that it reconnects. I find it does help to put pressure on the back of the case over where the card is.
I tried the thing where you put a small piece of paper in with the car to put a bit of tension on the connections. Hasn't really helped.
Any ideas?
|
|
|
|
Post by the light works on Mar 18, 2016 3:27:35 GMT
I got nothing. just the possibility of corrosion on the card or the contacts - which should not be a thing.
|
|
|
|
Post by silverdragon on Mar 18, 2016 6:56:52 GMT
This involves taking the back off.... so be bloody careful.
You will have the battery out, so no need for the usual warning of power off first?.
Gently, if you need to be told that, I suspect I may be teaching Grandma to suck eggs saying that?..
Gently clean the contacts with a q-tip cotton wool bud in some cleaning alcohol.
You mat need to squish that down to get under the contacts, or use a pair of tweezers wrapped in a tissue...
Remove any debris after that.
Same with Sim card?..
Inspect for damage. You may need to do that under magnification.
Hand out to dry..... and re-assemble when it is.
Because Sim cards are rarely protected by a cap. they can get dirt in there easily.
Have you tried swapping out with another sim card?.
They are not immortal, it may be your sim card has gone faulty.
Dependant on the environment, you can get dirt inside a phone extremely easily, and corrosion from battery off-gassing happens on the contacts?.. almost negligible, but over time, it can happen.
|
|
|
|
Post by the light works on Mar 18, 2016 13:55:04 GMT
This involves taking the back off.... so be bloody careful. You will have the battery out, so no need for the usual warning of power off first?. Gently, if you need to be told that, I suspect I may be teaching Grandma to suck eggs saying that?.. Gently clean the contacts with a q-tip cotton wool bud in some cleaning alcohol. You mat need to squish that down to get under the contacts, or use a pair of tweezers wrapped in a tissue... Remove any debris after that. Same with Sim card?.. Inspect for damage. You may need to do that under magnification. Hand out to dry..... and re-assemble when it is. Because Sim cards are rarely protected by a cap. they can get dirt in there easily. Have you tried swapping out with another sim card?. They are not immortal, it may be your sim card has gone faulty. Dependant on the environment, you can get dirt inside a phone extremely easily, and corrosion from battery off-gassing happens on the contacts?.. almost negligible, but over time, it can happen. all of my phones that have had SIM cards have had them fully enclosed. |
|
|
|
Post by silverdragon on Mar 19, 2016 8:57:58 GMT
Unless the pone is watertight, it aint air tight, and having worked in a clean room, I know how the smallest particle of dust can mess with electronics?... once you open the case, the sim card is usually under the battery, not the best location to be honest.
|
|
|
|
Post by the light works on Mar 19, 2016 9:06:31 GMT
Unless the pone is watertight, it aint air tight, and having worked in a clean room, I know how the smallest particle of dust can mess with electronics?... once you open the case, the sim card is usually under the battery, not the best location to be honest. they aren't hermetically sealed - but they do have a full closure. - and the batteries are integrated into the phone. they don't share a compartment. |
|
|
|
Post by silverdragon on Mar 19, 2016 10:00:49 GMT
Unless the pone is watertight, it aint air tight, and having worked in a clean room, I know how the smallest particle of dust can mess with electronics?... once you open the case, the sim card is usually under the battery, not the best location to be honest. they aren't hermetically sealed - but they do have a full closure. - and the batteries are integrated into the phone. they don't share a compartment. Then we need to identify the phone in question. If that phone has a removable battery, every time the battery is handled, it gets dirt transfer, which can transfer to the SIM. |
|
|
|
Post by wvengineer on Mar 19, 2016 11:07:54 GMT
|
|
|
|
Post by the light works on Mar 19, 2016 12:35:05 GMT
they aren't hermetically sealed - but they do have a full closure. - and the batteries are integrated into the phone. they don't share a compartment. Then we need to identify the phone in question. If that phone has a removable battery, every time the battery is handled, it gets dirt transfer, which can transfer to the SIM. yes, it is my own phones that have the closed SIM card compartments. I use Motorolas. |
|
|
|
Post by GTCGreg on Mar 19, 2016 15:10:35 GMT
Whenever metal is exposed to air, it can oxidize. Even gold oxidizes. The only difference is gold oxide is still conductive and will make contact. It doesn't necessarily have anything to do with dirt and dust.
Gold oxidizes the least. That's why it's often used for contacts.
|
|
|
|
Post by the light works on Mar 19, 2016 15:12:48 GMT
Whenever metal is exposed to air, it can oxidize. Even gold oxidizes. The only difference is gold oxide is still conductive and will make contact. It doesn't necessarily have anything to do with dirt and dust. silver oxide is also conductive. |
|
|
|
Post by GTCGreg on Mar 19, 2016 15:15:44 GMT
Whenever metal is exposed to air, it can oxidize. Even gold oxidizes. The only difference is gold oxide is still conductive and will make contact. It doesn't necessarily have anything to do with dirt and dust. silver oxide is also conductive. That's why silver is often used for relay contacts wear gold is just too expensive. And I believe gold also doesn't hold up well to arcing. |
|
|
|
Post by the light works on Mar 19, 2016 15:21:25 GMT
silver oxide is also conductive. That's why silver is often used for relay contacts wear gold is just too expensive. And I believe gold also doesn't hold up well to arcing. nothing does, really. |
|
|
|
Post by ponytail61 on Mar 19, 2016 22:36:08 GMT
I have a Samsung Galaxy S4 as by personal phone. It has had very few issues until the last few weeks. It seams to randomly loose connection with the SIM card. When it does so, it stops everything and you have to reboot and hope that it reconnects. I find it does help to put pressure on the back of the case over where the card is. I tried the thing where you put a small piece of paper in with the car to put a bit of tension on the connections. Hasn't really helped. Any ideas? Seems like a known issue. Here is a forum thread with the different fixes people have had success with. Seems many tried replacing parts to no avail, but something like a piece of thick tape or a guitar pic in the right place solved it. forums.androidcentral.com/samsung-galaxy-s4/276524-galaxy-s4-major-problem-sim-card-not-detected-8.html |
|
|
|
Post by OziRiS on Mar 20, 2016 1:44:00 GMT
I heard of this problem with the S4 the last time I went phone shopping. The S4 Mini doesn't have that problem, which is why I decided to go with that instead (plus it's smaller - I don't like the big, bulky phones).
Seems to be a design flaw in the S4 and I've even heard it carried over to some versions of the S5. Again, seems the S5 Mini doesn't have the same problem for some reason.
|
|
|
|
Post by c64 on Oct 30, 2017 19:06:54 GMT
Whenever metal is exposed to air, it can oxidize. Even gold oxidizes. The only difference is gold oxide is still conductive and will make contact. It doesn't necessarily have anything to do with dirt and dust. Gold oxidizes the least. That's why it's often used for contacts. Stainless steel or brass would be best to prevent corrosion. What makes gold superior is because it is soft. The contacts deform by pressure and this enlarges the contacting surfaces. Also dust "sinks" into the gold so the contact can still close. But it won't work by applying some gold to the surface. You need a very thick layer of gold. Most overpriced RCA (and HDMI) cables are not really gold. They are just dipped into "chemical gold" and the golden layer is just a few atoms thick. When I was 12 years old, I had installed a "CPU lock" on my C64. The CPU has an input line which stops the CPU. It is meant to allow the Video Chip to grab data. Every 8th video line (Next character line) is a so called "Bad line" where the CPU is stopped for almost half of the video line and the video chip can collect data from RAM to know what to display next. By soldering a switch between ground and this line, you can freeze your C64 which is neat when you need to grab something (or get rid of something else) while playing a game. I took a used toggle switch and bought a key switch and soldered them in in parallel. When using the toggle switch, every 3th time, the C64 had crashed. The key was fine, you had to switch it very fast multiple times to crash the C64. It took years to find out why. A general purpose switch has a thick lump of silver as the actual contact which is coated with a layer of gold. The gold minimizes bouncing and prevents corrosion. But gold can't handle arcing when switching higher voltages and currents (e.g. the mains). So a general purpose switch can be used for small signals OR power. When switching power for the first time, the gold burns away leaving the bare silver. Then it bounces a lot and needs power switched to keep the contacts clean from corrosion. So never use any salvaged switch where you don't know what it was used for to switch sensitive digital circuits! |
|
