When the iPhone 4 was released in June of 2010, it wasn't without it's share of glitches. The first reported glitch was with the iPhone 4's wireless 3G antenna. This was suspected to cause poor reception and a high volume of dropped calls. The next reported issue was with the iPhone 4's proximity sensor. Apple addressed this problem on the software level, with the release of iOS 4.1.
Since the iOS 4.1 release, there have been many questions as to whether or not the update resolved the iPhone 4 proximity sensor issue once and for all. From my own experience, I haven't had any complaints since this software update was made public.
Some of you may be wondering, "What in the world is a proximity sensor is and what function does it serve?" Without getting too involved, every iPhone (including the original iPhone 2G, 3G and 3GS models) have a proximity sensor. This sensor emits an infrared (IR) light that detects the presence of a solid object (such as a head or hand), while you have a call in progress, or while you are listening to a voicemail. When it detects a solid object, it turns your iPhone's LCD panel off. This is a function you'll probably never miss until it's no longer working.
The function of the proximity sensor actually has two distinct advantages. First, you aren't muting your phone, accidentally pushing buttons, or hanging up on your callers with your cheek. The other advantage is that it conserves power consumption and improves your phone's battery life in between charging cycles.
As an Apple Certified Macintosh Technician who makes a living supporting and fixing Apple products, this is an issue that could not be ignored. The reputation of my business hung in the balance of being able to find a reliable and professional solution for this problem. I've done extensive research and testing on this topic and feel like I've made significant headway in resolving this annoying glitch..
In the four years that I've been repairing iPhones, it's only been recently that I've began experiencing the problems that have been widely documented and reported. Since the release of iOS 4.1, I haven't seen any cases in which the iPhone's proximity sensor malfunctioned on a phone that hadn't been modified. When I say "modified" I mean a phone that has undergone a color conversion, or one that the front glass and LCD had been replaced due to the phone being dropped and having the original glass broken. I noticed that the occurrence was more apparent after a color conversions had been performed.
Since the proximity sensor on the iPhone 4 is located on the iPhone's mid-frame and is not a part of the front glass and LCD assembly, I had never questioned the quality of the parts I was purchasing. With that in mind, I began testing every phone prior to repair. I wanted to be sure that the phones were functioning properly, prior to repairs, or color conversions being made. So far, I have yet to find one that wasn't working just fine before the repair. It turns out, the problem was attributed to two factors.
1. The unique sensitivity of each iPhones proximity sensor.
2. The proximity sensor cover on some of the replacement glass is not tinted as dark. This allows too much light to pass through.
2. The proximity sensor cover on some of the replacement glass is not tinted as dark. This allows too much light to pass through.
I've read over many articles and blogs that suggest using black tape with holes punched out, or a black magic marker to cover the iPhone's proximity sensor. I didn't feel that either of these fixes offered a professional solution, or one that I would even be proud to employ in my practice.
After speaking with my parts distributor, I found the best solution for this problem is an inexpensive "sensor cover." This cover is a small piece of film with a coating that looks to be the same red polarized coating on some sunglasses. This small piece of film is installed over the top of the iPhone's proximity sensor.
At the end of the day, it would appear that too much light is getting in and confusing the phone. The proximaity sensor cover filters excessive light from entering the phone and there by solves the problem.
Lil' Johnny Appleseed is located in Kansas City, Missouri. We are a locally owned and operated company that specializes in repairing Apple Macintosh computers and iPhones that are out of, or not covered under the AppleCare Protection Plan offered to consumers of Apple products. We take great pride in the fact that we are the only Apple Certified Technicians in the Kansas City, Nothland area. We take even greater pride in the quality and care we provide each of our customers. We service and repair all makes and models of Apple computers and iPhones (including: iMac, Mac Mini, MacBook Pro, MacBook Air, Mac Pro, Power Mac, iPhone 2G, 3G, 3GS and 4).
