FRUs (Field-Replaceable Units)

FRUs (Field-Replaceable Units)

When you create your spare parts kit, most of what you include will be field-replaceable units, or FRUs. An FRU is any component that can quickly be swapped for another component. Standardizing equipment will help you reduce the number and variety of parts you need to stock.

If you have a bad component, such as a broken Ziff socket on a motherboard, or a bad ROM chip on an expansion card, you do not replace these components. Therefore they are not considered FRUs. For these components, you would be more likely to replace the entire motherboard or expansion card.

Types of FRUs:

• Floppy drives
• CD-ROM or DVD-ROM drives
• CMOS batteries
• Video cards
• CPUs
• Motherboards
• RAM

Mobile computing FRUs:

• Keyboard
• LCD panel
• CPU
• Floppy drive
• CD-ROM/DVD-ROM drives
• AC Adapter
• Battery pack
• Sound card
• Memory modules
• Pointing device

Tool Facts

• Loopback plugs are used to test ports by returning output signals as input.
• Null modem cables can be used to connect computers without network cards or modems.
• A multimeter measures electrical properties.
• A good fuse has no resistance and therefore reads 0 ohms when tested with a multimeter.
• A bad fuse does not allow electricity to pass through it and therefore reads 1 or infinity ohms.
• Multimeter settings:
• Ohms for resistance
• Volts for potential and current
• When troubleshooting, start with quick fixes first.
• Document the work you do. It will save time and money.
• Install and test one device at a time.
• Use compressed air, lint-free cloths, and solvents in the appropriate situations to maintain electrical contacts.
• Anti-static sprays, vacuums, cloths, and natural bristle brushes are effective cleaning tools.
• Reduce computer heat by cleaning dust from inside computers.
• Use a clean, dry rag to clean LCD monitors. Use alcohol-based wipes to clean CRT monitors. (You can also use 70% isopropyl alcohol to clean touch screen displays.)
• When components overheat, they produce a noticeable odor.
• To ensure the security of removable media, you can take the following measures:
• Lock the media in an office.
• Place the media in a locked cabinet (with strict key control).
• Place the media in a safe (or fire safe).
• Engage a third-party firm to store the tapes in its secure facility.