"No sim card"

[tjansen]

I have a Lenovo B6000-HV tablet. My Dtac sim card worked in it yesterday, and it still works in a nokia cellphone. Today neither that sim card nor another working sim card appears to be able to be detected by the tablet. All I did was put the sim card in my nokia to copy contact numbers from the phone to the card. When I re-installed it, I got the message No sim card, emergency calls only.

Any help out there? I searched the Android forums to no avail.

Thanks.

Tom

[RichCor]

Could be one of many posibilities.

Maybe you damaged the SIM card slot when you removed or inserted the SIM.

Updating the SIM may have cause your B6000-HV into an odd state.

Some people complain the the SIM slot is backwards. Make sure to insert in direction per the graphic.

Try powering the device off, let it set for a while, power back up with the old or a new SIM.

If that doesn't work after 10 tries you may need to fully reset the tablet.

Wipe Date / Factory Reset (All data wiped, reset tablet to day one)

Technique: Wipe Data / Factory Reset (Hard Reset)

[tjansen]

Thanks a lot for the suggestions. I will back up my data, then start trying things.

[dddave]

And just to make sure some schmutz didn't fowl the contacts on the SIM, clean it with a pencil eraser.

[tjansen]

I am the OP, and I have further developments. I decided to bite the bullet and start off with a factory reset, as mentioned by RichCor. I had already tried shutting off and letting it sit, although not for ten times.

After the reset, it still didn't work. I took it to DTAC, and they cleaned the sim card with an eraser, as suggested here by DDDave. They did some other things in the back room, but all to no avail. They tried another sim card they had there, and it didn't work.

Here is the tricky part. I took it to a phone shop that I used to buy pre-pay from, and he tried a sim card in it that worked. I would have stopped right there and switched to his prepay, but I want to keep the same number, and I don't think I can do that with a pre-pay account. I haven't confirmed that, which I need to do.

It appears that it is a marginal problem. Recall from my original post that this sim card was working in the tablet, even when I switched it to my nokia dumb phone and back again. It stopped working in the tablet when I installed it in my nokia, copied my contact numbers from the phone to the card, and then re-installed it in the Lenovo tablet.

I know buying a Samsung or ?? smart phone is the easy solution. I am just trying to defer that expense for as long as I can. I use the tablet mostly with wi-fi at home. I just want the sim (with the same number) for occasional internet use and virtually no phone calling.

Any ideas will be appreciated.

EDIT. One further occurrence. Grasping for straws, I decided to delete all the contacts from my sim card (using my nokia cellphone), since adding a lot of contacts to the sim was the last thing I did before it stopped working. I was asked for a security code to complete the deletion. I called DTAC to ask them about this, and they said to use the code that I had my phone locked with. When I told her I didn't have it locked and had no code, she told me to try 1800, which didn't work.

Tom

Edited January 8, 2016 by tjansen

[RichCor]

What SIM did your TopUp shop put in?

If you bought a DTAC SIM that works, then you could take that to an official DTAC Shop and have them place that SIM on your account (keep the same telephone number). I've done this before, when we've lost a phone. The account just needs to be registered and you show the same registered documents to prove ownership.

The Lenovo B6000-HV tablet supports:

2G bands GSM GPRS/EDGE Data: 900 (band 3) / 1800 (band 8) / 1900 (band 2)

3G bands UMTS/W-CDMA/HSPA: 900 (band 3) / 2100 (band 1)

DTAC Network supports:

2G bands GSM GPRS/EDGE Data: 1800 (band 8)

3G bands UMTS/W-CDMA/HSPA HSPA+ 850 (band 5) / 2100 (band 1)

Whatever SIM you use needs to support the same, preferably 3G frequency. So...

900 (band 3) was previously controlled by AIS, recently shut down and auctioned off to TrueMove H and JAS for 4G.

2100 (band 1) is good for 3G using AIS, DTAC, TOT3G, TrueMove

[tjansen]

This sounds like a possible solution, but I got lost with your description. I think the shop sells DTAC prepay. That is what it was when I used their service in the past.

So, exactly what do I tell him when I am buying the new sim card that works, and exactly what do I tell DTAC when I go to their shop.

Will that new sim card be changed to my existing (DTAC) phone number? I don't think I will have a problem with identifying myself. I had to produce my passport when I got this sim card, and I assume they have that paperwork on hand.

Thanks a lot for your trouble.

Tom

What SIM did your TopUp shop put in?

If you bought a DTAC SIM that works, then you could take that to an official DTAC Shop and have them place that SIM on your account (keep the same telephone number). I've done this before, when we've lost a phone. The account just needs to be registered and you show the same registered documents to prove ownership.

The Lenovo B6000-HV tablet supports:

2G bands GSM GPRS/EDGE Data: 900 (band 3) / 1800 (band 8) / 1900 (band 2)

3G bands UMTS/W-CDMA/HSPA: 900 (band 3) / 2100 (band 1)

DTAC Network supports:

2G bands GSM GPRS/EDGE Data: 1800 (band 8)

3G bands UMTS/W-CDMA/HSPA HSPA+ 850 (band 5) / 2100 (band 1)

Whatever SIM you use needs to support the same, preferably 3G frequency. So...

900 (band 3) was previously controlled by AIS, recently shut down and auctioned off to TrueMove H and JAS for 4G.

2100 (band 1) is good for 3G using AIS, DTAC, TOT3G, TrueMove

[RichCor]

I think the shop sells DTAC prepay. That is what it was when I used their service in the past.

So, exactly what do I tell him when I am buying the new sim card that works, and exactly what do I tell DTAC when I go to their shop.

Will that new sim card be changed to my existing (DTAC) phone number? I don't think I will have a problem with identifying myself. I had to produce my passport when I got this sim card, and I assume they have that paperwork on hand.

Thanks a lot for your trouble.

Tom

Seems you've said that you've tried 'other' DTAC SIM Cards that refuse to be recognized in your tablet, but fount one the did.

Apparently, the tablet does work with a DTAC SIM, just not every DTAC SIM (for whatever reason).

You have a couple of choices, as you need to find a DTAC SIM Card that will actually work in that device, and hopefully have it work using the DTAC phone number you already have. So, if you want to keep DTAC as the mobile provider:

1. Buy that exact SIM, or one like it, that works and use the new number that came with it.

2. Buy the SIM, but take it to an authorized DTAC shop and ask then to assign it to your DTAC account that's using the phone number you want to keep. They keep the old SIM Card, you use the new SIM Card but now it works with your previous phone number.

3. Go to the authorized DTAC shop and tell them your tablet doesn't work with this SIM Card any more, but will work with a new SIM Card, and could they please give (or sell) you a new SIM Card that works and assign it to your previous phone number.

I know they can assign the new SIM to replace the existing SIM Card, as I've done this before. Even if they don't use that SIM and instead use some other SIM Card they have, as long as it works and uses your previous phone number... that's what matters.

I'd suggest you try option three, but if that doesn't work then fall back on option two, or one. You already know there is a SIM Card that will work.

The rest of my post was just technical gibberish. Ignore it if it's not useful.

[tjansen]

Hello again RichCor,

Well, the problem has been partially figured out and partially resolved. It is looking like your "technical gibberish" is proving to be very relevant.

I went to the phone shop yesterday (The owners are very friendly to me. I bought my (now lost) Samsung smart phone from them, and they have sent their kids to my girlfriend's English tutorial school). The owner took my tablet and went to the DTAC store to find out what was going on. It turns out that my tablet is only good for the (old) 2G sim card, so he brought it back, and they gave me a 2G sim card that they had. So now the tablet works on the 'network', but with a different number.

DTAC didn't tell me that the vintage of the tablet was the problem; they just acted like it didn't work. The fact that it did work for a few days tells me that it becomes incompatible with 3G by the flip of a switch, rather than a characteristic of the phone. I recall in the past having to switch sim cards because of some similar occurrence. In that case, there was a 'grace period' in which the old sim card still worked. All this tells me that it is, from my perspective, planned obselence. Oh well.

Back to what you know and have recommended. First of all, I haven't gone to DTAC yet to see if I can get that old sim card switched to my current DTAC sim phone number. I will probably do that in the next couple of days. Today I will go the the phone company and give them my documents to get the sim switched to my name.

Out of curiosity, I went to True and asked them if they had a 2G sim card, thinking I could switch to their service.. They said no, I would have to change.

Anyway, I saw in your previous message a reference to some combination of either 2G or 3G that might make my tablet work with some (???) provider. As before, I didn't follow what you are saying, but now I am asking if that bears investigating, after, of course, I check with DTAC to see if they can 'adopt' my new/old sim card into my post pay account.

Thank you for all of your help and education on some of the intricacies of the phone / Internet era.

Tom

I think the shop sells DTAC prepay. That is what it was when I used their service in the past.

So, exactly what do I tell him when I am buying the new sim card that works, and exactly what do I tell DTAC when I go to their shop.

Will that new sim card be changed to my existing (DTAC) phone number? I don't think I will have a problem with identifying myself. I had to produce my passport when I got this sim card, and I assume they have that paperwork on hand.

Thanks a lot for your trouble.

Tom

Seems you've said that you've tried 'other' DTAC SIM Cards that refuse to be recognized in your tablet, but fount one the did.

Apparently, the tablet does work with a DTAC SIM, just not every DTAC SIM (for whatever reason).

You have a couple of choices, as you need to find a DTAC SIM Card that will actually work in that device, and hopefully have it work using the DTAC phone number you already have. So, if you want to keep DTAC as the mobile provider:

1. Buy that exact SIM, or one like it, that works and use the new number that came with it.
   
2. Buy the SIM, but take it to an authorized DTAC shop and ask then to assign it to your DTAC account that's using the phone number you want to keep. They keep the old SIM Card, you use the new SIM Card but now it works with your previous phone number.
   
3. Go to the authorized DTAC shop and tell them your tablet doesn't work with this SIM Card any more, but will work with a new SIM Card, and could they please give (or sell) you a new SIM Card that works and assign it to your previous phone number.

I know they can assign the new SIM to replace the existing SIM Card, as I've done this before. Even if they don't use that SIM and instead use some other SIM Card they have, as long as it works and uses your previous phone number... that's what matters.

I'd suggest you try option three, but if that doesn't work then fall back on option two, or one. You already know there is a SIM Card that will work.

The rest of my post was just technical gibberish. Ignore it if it's not useful.

[RichCor]

SIM Cards sometimes get updated with new network information Over-The-Air.

With the recent changes to spectrum owners in 900 and 1800 in December then that's probably what happened. There were no changed to DTACs spectrum allocation, so it's odd your tablet wouldn't work with that SIM but your other phone would.

There is a difference in how PrePay and PostPaid SIM Cards are provisioned ...but it shouldn't have an effect on how the phone accessed the available 2G or 3G network.

2G is going away.

But there are still a LOT of 2G only hardware out there in subscriber's hands that can't run on the 3G or 4G networks.

The Network Operators (mobile providers) are trying very hard to get subscribers to swap-out or buy compatible 3G or 3G/4G/LTE equipment, as they shrink their existing 2G services provided on their towers to provide more 3G or 4G radio spectrum to their newer subscribers. They don't want to enable any additional 2G subscribers.

As previously stated in the technical gibberish, your tablet has two network radios:

2G 900 / 1800 / 1900 MHz

3G 900 MHz (band 8) -- was previously controlled by AIS, recently shut down and auctioned off to TrueMove H and JAS for 4G.

2100 MHz (band 1) -- is good for 3G using AIS, DTAC, TOT3G, TrueMove

So I expect your tablet to work with Voice and super-slow Data on 2G 1800MHz until DTAC eventually turns off their 2G network support.

Your tablet IS capable of 3G (UMTS / W-CDMA / HSPA / HSPA+ network types) on 900 and 2100 MHz radio frequencies, so SHOULD work 2100 (band 1) with AIS, DTAC, TOT3G and TrueMove-H ....unless something happened to your tablet's 3G BaseBand Radio, leaving it with only with 2G BaseBand Radio operating.

I suggest you try one of the other provider prepay 3G SIM Cards (AIS, TOT3G, TrueMove-H) and see if one of them bring up 3G network, just to make sure the tablet 3G baseband radio still works.. Sometimes you can get the SIM cards for free (or very low cost), put a 10-30 baht on the account and enable 3G data on the device and see what happens.