Simple Trick To Fix iPhone 4 Reception Issues?

iPhone 4 signal reception caused by SIM

Folks at MacRumors have published an interesting fix to the signal reception issue that has plagued the new iPhone 4 since launch.

According to a message posted by one of their forum members, the reception issue could be potentially fixed by merely taking the SIM card out of the tray, re-seating it and then reinserting it.

The iPhone user, who posts under the handle jav6454, writes:

"My iPhone suffered from the same green spot effect as the iPhone from the user on MacRumors. Knowing full well, it was a hardware problem I set up an appointment for today at 6:30 PM…the Genius reswaped the SIM card to my phone back and handed it to me. (My iPhone spent 15 minutes with out SIM card while the Genius did all his tests on my and replacement unit, and while he asked for 2nd opinions on the green blob issue)

I went on my merry way, but realized something now. No matter what position I held my iPhone 4 in, the signal never decreased. I held it the many ways I know the signal issue pops and nothing. No bar loss, no signal loss, no call drop. NOTHING. So there you have it. 

I am theorizing that moving the SIM card had something to do with the signal issue, because the only thing I have done to my iPhone 4 differently is take out and reinsert the SIM card. Other than that no other changes to it. No setting change, no software change no nothing. Just reinsertion of the SIM card."

Surprisingly, quite a few users have responded claiming to have seen significant improvement in signal reception by using this fix. However, it also needs to be noted that an equal number of users do not seem to have observed any change.

According to one of the members, the root cause for the reception issue may lie with the way the SIM Card is aligned on the SIM tray. He writes:

"The metal part of the sim card is not centered and is contacting the sim tray. The sim tray is steel and the sim tray is contacting the outer antenna band. Once you touch the phone, this could be causing a sim issue. If when you touch the antenna line on the lower left it changes the state of frequency, power or what ever, it might actually be messing with the sim card. The metal on the sim is connected to the sim tray, the sim tray is connected to the antenae and the antenae is connected to your hand when you touch the phone. Take a look at your sim card and see if the metal is just off center enough to touch the tray."

iPhone 4 signal reception caused by SIM

MacRumors points out that users who tried to isolate the SIM from the tray with the help of an electrical tape or by cutting the SIM on the opposite side have reported mixed results. Considering that nearly half of the users who have tested this fix did not notice any change, we may have to stay skeptical for the moment.

However, we will be interested to see if this fix works for our readers as we don't see any harm in trying it out. Do try this on your iPhone 4 and let us know if you notice any significant improvement in signal reception.

[via MacRumors Forums]

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  • Des Dew

    So I did what was suggested and the reception issue did go away. However, I don't think it is a pulling the SIM out and putting it in, rather a re-seating of the SIM that is doing it. Who knows… but it seems to have worked on my iPhone 4!

  • Thomas

    Best fix is for apple to admit there is a problem, work on it and somehow compensate those who purchased the phone.

  • Thanks Des for the inputs, updated the post.

  • Shomtech

    I can confirm this does work I took my 3Gs simcard out and cut it down to micro sim size put it in iphone4 it didn't work right I took it out and pushed the card over some have not have not 1 problem since no matter how I move or hold the phone

  • brundon

    nope i tried this when i first had the issue not helping my phone at all…

  • Did you re-seat the SIM as well as Des as suggested?

  • I SAY

    NO.i even put some tape to confirm its not touching any metal surface and it still goes down all the way with the death grip

  • Algonn

    is this problem only in the US or it is also in the other counties where iphone 4 released?

  • joe bob

    Just tried this on my iphone4…Worked like a charm!!

  • jeepfan30

    I tried re-seating my SIM three times and still have the issue. Just buy a case…no more reception issue and you dont have to stand in line and pay $600 to get a new phone when you drop it.

  • sacapuntas

    ok this worked for me to a point. after reseating the sim i cant get it to drop more than 2 bars. so at least it maintaining 3 bars now instead of dropping to zero.

  • Nonoie

    not for my iphone 4g… tried so many times does not work for mine.. ty though

  • Brundon

    I just did the tape method and still no change drops bars just as fast as ever.. This is not a fix

  • this guy

    It works! Went from 2 bars up to five. Still need to test it outside and some other places though..

  • jaycee

    Hey i dropped my iphone 4 (goodthing it was carpet) any how the sim popped out accidently, and now its working fine, no matter the position i hold it, signal stays stable 🙂

  • I tried putting the sim again , no luck but i notice that each time i insert the sim i get good signal then even if i leave it , the signal drop . In addition this is my second iphone as i replaced the first one with apple store and i have a bumper and the signal is terrible. May be its vodafone in UK or may be its the iphone it self .

  • Jcm800

    Frankly Vodaphone are bottom of the league for reception, at least in my town. Plus, if this was a proper fix, then the signal issue wouldn't be affecting ppl that have a 3gs with ios4 installed?
    Just a thought..

  • iPhoneDev

    This could be a SMT soldering issue on the SIM socket connector. The change in pressure from removing the sim card and re-inserting it might be enough to change the solder connection. This is not uncommon with sim card sockets that are ultra-fine pitch.

  • colton

    iPhone 4 not 4g

  • nubs

    hmm so your saying if the try was plastic instead of metal it could possibly fix some of the iphone 4s out there? or just higher standards on sim card production?

  • didnt work for me… but I got a case anyway, so I dont care…

  • Lividhatter

    didnt work for me either, i will say that the chip part of my sim does seem to touch the tray, or come EXTREMLY close to the tray.

    perhaps if the chip part of the sim was centered, life would be better?

  • It worked for me…

  • iphonejeff

    nope, tried putting electrical tape on the edge were the sim card touches the sim holder and still, bars drop from 5 to 1.

    it just seems to be an issue of antenna placement. maybe apple can adjust the sensitivity in software.

    I seem to recall something similar to this on the 3g, where you would see a 1 or 2 bar drop.

  • x52

    Worked for me!

  • I4

    Did nothing for me. I even covered it up with tape to make sure there is no contact and still drops signal just as it did before.

  • Brundon

    Just called apple and spoke with a sup. They said they have just recently been given news that it is a hardware issue and its the antenna its self. I mentioned the sim issue and he said that is not the issue its the phone its self. At least they can admit it. Also i was told i could have a free bumper from a rep who then transfered me to the sup and he said that apple has done their research and the bumpers are not a fix, it has to do with body chemistry and that very few people will see a fix with the bumper. Hope this helps some

  • Sauce

    Half worked for me, I don't get the complete drop out anymore, but it still drops.

  • Angelo

    Try to get a plastic Sim tray (if it works)…like on 3gs..
    or paste a small thin piece of tape on the Sim tray or the sim card which might connect to gather..

    + does any one out side the US experiencing similar issues or this is only for US iphones?

  • Brooke

    Tried this 4 different ways and still no change in my signal drop.

  • its not affecting 3gs users…

  • Nobber

    Even if it works, you shouldn't have to do this to a £500 phone to make it function as it should. And what about the proximity sensor problems?
    Apple sort it out!!!!

  • Daz

    Just tried this little trick and I must admit it does help the signal strength quite a bit.
    I'm on the o2 network in the UK, in the house I was getting zero bars in some places, now I'm getting 4 !!, I just placed sticky tape on the edge of one of the sides of the sim tray,might try the other side now see if that does the trick !
    Cheers for the tip, I did see the same tip posted over at sinful iphone earlier today though !!

  • Fahad

    I don't have any reception problem with my iPhone since I get it on 24th of June as I cut my SIM my self.
    guys, do you really have reception issue, please answer with yes or no and mention where are you from

  • Seems to have worked for me. When I pulled my sim out, I had 3 bars of signal. Now that I reseated it, I have full signal.

  • It definitely worked for me! I was even noticing some speed issues before as far as the connection, because when I connected to my boy's JB 3GS through MyWi Wifi to DL something from the App Store, it went so much faster. That bugged me out, so I downloaded the app, and I was clocking anywhere from 6kbps to 303kbps on my own connection, with an average of about 60kbps. I then reconnected to my boy's phone and immediately clocked 1.3MBps. After re-sitting the SIM, my "hold the phone this way" problem is gone, AND I just clocked 2.2MBps on my own 3G connection. THANKS A LOT!!

  • I live in Bath Uk and my iphone 4 on vodafone . and i have a terrible signal all the time when im not out door.

  • Steven M

    Did not work for me. Here is what we need to figure out. There are actually two different issues that are getting mixed up. The "deathgrip" and connecting the antennas are not entirely the same thing. One does cause the other though. The "deathgrip" on the iPhone 4 causes the connection to be made, but even without the connection being made the "deathgrip" still affects the signal.

    For those saying your phone is fixed please do this. Lay your phone on its side with the left side up. Place a quarter over the black line connecting the two antennas. If this does not cause the signal to drop I will believe that your phone is fixed. Also, if anyone can post a video of them placing a quarter over that spot without a loss of signal, I will have hope that this isn't entirely a design flaw.

    The reason I say these are 2 different issues is the "deathgrip" affects all phones. When you hold a phone you will lose some signal. This is the fact of life that Steve Jobs was talking about. Making the connection between the 2 antennas is iPhone 4 specific. Gipping the phone not only causes regular signal loss but also connects the antennas causing a bigger problem.

    So if you think you've fixed your phone by reseating the sim please let us know your results with the quarter.

  • CM

    I tried re-seating and that didn't work… I had the same thought about the plastic tray and/or a piece of tape… I have to say… a tiny piece of electrical tape does wonders.

  • Ashenden

    Hurr hurr guys do you really have reception issues or are you all making it up, please tell me! Stfu.

  • Jcm800

    Yes it is. it's affecting 3GS users that have uprgraded to ios4.
    So it's clearly not just the antenna.

  • NightHawk

    I put a lil piece of plastic in my SIM tray put it back in and it said "NO SIM"
    Any thoughts on that one?

  • Katatonia

    I will let everyone here know right now, calling apple reps WILL not help you one bit,most of us are all newbies and we are telling you the same shit that we read off of blogs like this one.

    the only real thing you can do is be happy you got a sweet phone that can take really nice videos, and wait for further notice on what is actually released to the public.

    the internal comments that you can read in the previous blogs are how we are to position bumpers/reception TO YOU, the only reason they were made was because of blogs LIKE THIS that got you motivated to call us about issues we already know about.

    Sit tight and calm down, please.

  • Jcm800

    Hate to rub it in, but i can't help thinking Vodaphone's crap 3G network is contributing to your problems.

  • 3gs

    OMG Colton, how fucking nice for you to press through all the post for this mistake. You act like he called your mama a slut or something.. CHILL

  • 3gs

    You're an idiot too..

  • Says who? This Haven't seen any complaints about their reception being worse because they updated their os. I for one have had better signal all away around since updating. This has nothing to do with the os.

  • Ejmelby

    A lot of people are noting that the sim card in the metal tray is too close to the contacts and thinking it is shorting it out. Upon closer inspection of my sim card tray, there is a plastic, insulation sticker that prevents the sim card contacts to be shorted out. The sim card shorting is not the problem. I too have the signal problem when my bumper is not installed, even after sim card reseat. I would hope this is addressed soon by apple.

  • I SAY

    holly fuck!!!! i tried it one time.. it didn't work..the bars would still go all the way down to one… I decieded to try it one more time and now no matter how hard I grip or hold it… it wont move any bars down!!!!.. the first time I put some tape to make sure it didn't touch the metal at the tray… put it back and it will still go down… 4 hours later. i tried it again .. took the tape out.. replaced the sim card and this thing wont drop a mm!!! its awesome…No matter how I grip it.. it wont go down.

  • I SAY

    dont put plastic that would cover the metal parts of sim completely, make sure they at least touch… i did same thing but with tape

  • Sahid

    im tried it.. it works… I get full bars nomatter what. will post video in a little bit..

  • Sahid

    I managed to fix it by resitting the sim card… here is proof:

  • Sahid

    I managed to fix it by resitting the sim card… here is proof:

    now will you believe it?

  • Steven M

    Haha, that is awesome! Exactly what I wanted to see. I was beginning to think nobody was going to try that. Thanks! Not only did you try it but you proved it with a video. I tried reseating mine with no luck. Maybe the fix will be a replacement sim with the contacts more in the middle. This gives me hope and I believe that this fix worked for you. Now if it is still working like that tomorrow we'll know for absolute certain this fixes the issue. Thanks again.

  • Steven M

    Nice! Maybe I should try it again. I just hate to remove and insert my sim card more than necessary. My gold contacts definitely touch the sides but I don't think there is much I can do about it other than replace the sim with another one that is more centered.

  • Zulfly

    This did not work for me, did the small sliver of tape also. note, I did this in my basement, where signal is weakest. Went from 5 bars to 1.

  • Jcm800

    Says ppl on this site, read around

  • NateDawg

    it also doesn't help that a 20db decrease in signal strength at full five bars still shows five bars of signal strength, but a 20db decrease at 4 bars will get you all the way down to 1 or no bars of signal strength. logarithmic decrease of signal strength to signal bars….

  • ZeppelinLed

    Has anyone tried painting the join line with clear Lacquer or Nail varnish yet?
    I think a couple of coats of either would be hard to see, but would also break contact succesfully?

  • Nobber

    Doing it in your basement isn't very bright. It's like smoking a cigarette on a fast motorbike-a stupid idea.

  • FW190

    Maybe the white ones are being modded as we speak, or maybe not..

  • long tall texan

    'in my basement' wtf? douchebag city bigtime.

  • John

    If you hold it through piece of paper does it lose reception as well? If not maybe very thin isolation would be enough like a nail polish or sth like this just paint it a bit to get the isolation. Try it at your own risk.

  • anshul

    when Dev team is planning to release jb f0r 3gs running ios 4 (new bootrom) ????

  • haris

    can the iphone 4 be unlocked/jailbreaked??

  • Get it right!

    Get a grip cock house! It's not an iPhone 4G it's an iPhone 4! Likewise apple don't make iTouch's and mcdonalds don't sell Chicken McSandwich's! You wouldn't call an Xbox 360 an Xbox 370 would you! Dick!

  • Matt

    FIXED 🙂
    I removed the sim, placed some brown parcel tape around the side of the tray where it touches the copper part of the sim.
    My signal npw only drops one bar when holding the phone tightly in my left hand.
    Thanks 🙂

  • On my 3GS, all I need to do is turn on airplane mode, let it sit in airplane mode for 10sec or so, then switch back to regular mode. This resets the signal and everything works perfect after.

    Hope this helps.

  • Disgruntled.

    Has anyone noticed that their old 3gs had a louder output volume when playing songs on the iPod?? Another bloody glitch..

  • Bob


  • Rob

    SAME HERE!!! Wow, best 2 seconds ever so I can hold my phone normally. Will post back if the issue is not actually fixed. Thanks!!!

  • Rob

    Just Joking, must have been the reset.

  • Larry

    When this problem was first noticed, I fixed it by filing the edge of the sim tray where it touched the sim contacts just a little so there was a small gap between tray and contacts. when I made sure I could not slide the sim over and make contact again I put sim and tray back in phone. No more loss of signal as before. Did the same for my wife's phone and it also works great now. This is a very easy fix and seems to be the cure. Good Luck to all.

  • Teik

    Tested this theory and confirmed it has some improvement.
    the 3G download speed was Maxed at 300Kbits/s but after i put a piece of tape along the sim-tray, the download speed increase to Max 844 kbits/s, tested several times.
    Taken screenshots ect.
    Just want to say thanks and letting other knows it somehome has improved but i need to test again when i get home from work since it is worst at my place.

  • Thanks-a-mundo for the writing.Thanks Again. Superb.