苹果Apple笔记本维修故障现象：1、 苹果Apple笔记本电脑不启动，开机无显示。2、 苹果Apple笔记本电脑密码遗忘，无法进入系统。3、 苹果Apple笔记本电脑不认光驱、硬盘、软驱、串口、并口等。4、苹果Apple 笔记本电脑无法安装操作系统。5、 苹果Apple笔记本电脑经常死机、掉电或自动重启。6、苹果Apple 笔记本电脑开机报错，无法进入系统。7、 苹果Apple笔记本电脑电池无法充电。苹果Apple笔记本服务项目及设备：A：软件调试及系统恢复（可编程仿真器：是对固化芯片上的程序进行读写和编辑，修复程序问题引起的故障）B：更换LCD显示屏，修理暗屏。C：清除开机密码，BIOS密码。D：光驱CD、CDRW、COMBO、DVDRW、FDD软驱、HDD硬盘、键盘、电池（维修、更换） E：机器内部除尘，维修"开机无显示"故障。F：（BGA球棚阵列焊接台：对于球棚阵列封装方式的芯片进行拆装）对笔记本主板进行维修。硬盘：修复硬盘数据G：笔记本升级：扩内存、硬盘、CPU等，提供升级方案。列封装方式的芯片进行拆装）对笔记本主板进行维修。硬盘：修复硬盘数据
好多年没玩苹果的电脑了，没记错的话开机按住option+R键，帮你找了下：参考苹果：
Reinstall from macOS Recovery
macOS Recovery makes it easy to reinstall the Mac operating system, even if you need to erase your startup disk first. All you need is a connection to the Internet. If a wireless network is ailable, you can choose it from the Wi-Fi menu in the menu bar. This menu is also ailable in macOS Recovery.
1. Start up from macOS Recovery
To start up from macOS Recovery, turn on your Mac and immediately press and hold one of the following combinations on your keyboard. Command-R is generally recommended, especially if you never installed macOS Sierra 10.12.4 or later.
Command (?)-R
Install the latest macOS that was installed on your Mac.
Option-?-R
Upgrade to the latest macOS compatible with your Mac.
Shift-Option-?-R
Install the macOS that came with your Mac, or the closest version still ailable.
Release the keys when you see the Apple logo, a spinning globe, or a prompt for a firmware password. When you see the Utilities window, you've started up from macOS Recovery.
macOS Utilities window
2. Decide whether to erase (format) your disk
If you need to erase your disk before installing macOS, select Disk Utility from the Utilities window, then click Continue. You probably don't need to erase, unless you're selling or giving away your Mac or he an issue that requires you to erase. Learn more about when and how to erase.
3. Install macOS
After starting up from macOS Recovery, follow these steps to install macOS:
Choose Reinstall macOS (or Reinstall OS X) from the Utilities window.
Click Continue, then follow the onscreen instructions to choose your disk and begin installation.
If the installer asks to unlock your disk, enter the password you use to log in to your Mac. If it doesn't see your disk, or it says that it can't install on your computer or volume, you might need to erase your disk.
macOS installer window
Please allow installation to complete without putting your Mac to sleep or closing its lid. During installation, your Mac might restart and show a progress bar several times, and the screen might be empty for minutes at a time.
If your Mac restarts to a setup assistant, but you're selling or giving it away, press Command-Q to quit the assistant without completing setup. Then click Shut Down. When the new owner starts up the Mac, they can use their own information to complete setup.
