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iDevice Repair Best Practices

This chapter takes care of some literal and figurative housecleaning that any self-respecting iDevice technician should undertake before performing any DIY work on iDevices.

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I’m talking about answers to questions such as the following:

  • square-blue.jpg How can I determine whether an iDevice is in or out of warranty?
  • square-blue.jpg What do those strange acronyms like IMEI and ICCID mean?
  • square-blue.jpg What’s the difference between an iDevice Model Number and an Order Number?
  • square-blue.jpg What do the strange hieroglyphics on the back of my iDevice represent?
  • square-blue.jpg How can I maximize the safety effectiveness of my repair workshop?

Those are some juicy questions, don’t you agree? What are you waiting for? Let’s get to work!

Checking iDevice Warranty Coverage

Whenever you are presented with an iDevice and are asked to perform an out-of-warranty repair, the first thing you should do is definitively verify the actual warranty status of the device. Fortunately, you can easily find an answer to this question in ways that we will discuss now.

If you can’t start the iDevice, then you can obtain the serial number, from the original product packaging or in iTunes. (You can find instructions for locating the serial number in iTunes in the sidebar later in this section.)

You can check your iDevice serial number in iOS 6 by navigating to Settings, tapping General, and then tapping About. This interface is shown in Figure 4.1.

Figure 4.1

FIGURE 4.1. We can determine an iDevice serial number from within iOS.

You can also submit the device’s serial number to Apple’s Check Your Service and Support Coverage page (https://is.gd/C8pEzh). The resulting web page, shown in Figure 4.2, provides you with the following information about the given device:

  • square-blue.jpg Device purchase date
  • square-blue.jpg Telephone technical support status, along with expiration date
  • square-blue.jpg Repair and service coverage status, along with expiration date
    Figure 4.2

    FIGURE 4.2. You can determine iDevice warranty coverage by visiting Apple’s website.

The format of the iDevice serial number is a combination of non-unique and unique information. It really does not behoove you to attempt deciphering Apple’s serial number format because (surprise, surprise) Apple changes the format on a semiregular basis.

Instead, if you would like a breakdown of a given iDevice’s serial number then I suggest that you visit the Dutch website Chipmunk International BV (http://is.gd/8BnvUi) or EveryMac.com (http://is.gd/wNrlgV). You can submit your device’s serial number and obtain a list of detailed metadata concerning the origins of the device. This metadata includes the following:

  • square-blue.jpg Year the model was introduced
  • square-blue.jpg Production year
  • square-blue.jpg Production week
  • square-blue.jpg iDevice model name
  • square-blue.jpg Order Number
  • square-blue.jpg CPU speed
  • square-blue.jpg Screen size
  • square-blue.jpg Screen resolution
  • square-blue.jpg Case color
  • square-blue.jpg Capacity
  • square-blue.jpg Factory of origin

To quote Miguel de Cervantes from his wonderful novel Don Quixote, “Forewarned, forearmed; to be prepared is half the victory.” With that in mind, let’s continue on the journey to iDevice metadata enlightenment.

Verifying iDevice Version Info

As you know, Apple has historically not been precise, much less consistent, in its product naming. For instance, consider the iPad. These are the official product names for the three generations of iPad:

  • square-blue.jpg iPad
  • square-blue.jpg iPad 2
  • square-blue.jpg New iPad

Give me a break! What makes matters worse is that all three generations have simply iPad etched on the back panel.

The same goes for iPhones; remember our previous discussion of iPhone 3G, 3GS, and iPhone 4S? What relationship do those product names have with 3G or 4G carrier network connectivity? You have to consult a reference table to answer that question.

The most reliable method for identifying a particular iDevice model is to ascertain its model number. This alphanumeric string is printed on the rear case of the device (see Figure 4.3).

Figure 4.3

FIGURE 4.3. You can determine the iDevice model number and other metadata by viewing the rear case.

Use Table 4.1 as a reference to determine a model number.

TABLE 4.1. iDevice Model ID Reference Table


Model ID

iPhone 3GS


iPhone 4 (GSM)


iPhone 4 (CDMA)


iPhone 4S


iPhone 5 (GSM)


iPhone 5 (GSM and CDMA)


iPad 1st generation Wi-Fi


iPad 1st generation Wi-Fi/3G


iPad 2nd generation Wi-Fi


iPad 2nd generation Wi-Fi/3G (AT&T)


iPad 2nd generation Wi-Fi/3G (Verizon)


iPad 3rd generation Wi-Fi


iPad 3rd generation Wi-Fi/4G (AT&T)


iPad 3rd generation Wi-Fi/4G (Verizon)


iPad 4th generation Wi-Fi


iPad 4th generation Wi-Fi/LTE (AT&T)


iPad 4th generation Wi-Fi/LTE (Verizon)


iPad mini Wi-Fi


iPad mini Wi-Fi/LTE (AT&T)


iPad mini Wi-Fi/LTE (Verizon)


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