Day 15. Hardware Troubleshooting, Part 2

Objective 4.6: Given a scenario, troubleshoot printers with appropriate tools.

Laptops can be upgraded by adding memory or replacing the hard drive, and sometimes broken parts such as display inverters can be replaced. Many laptops offer access to internal components by removal of the keyboard or by opening an access panel under the unit. Other components can require a complete disassembly—for example, removing the motherboard.

Here are a few common steps you can take to troubleshoot most mobile devices including laptops:

Check/change configuration settings.

Check/change the batteries.

Reestablish wireless connections.

Uninstall/reinstall applications and operating systems.

Close all running applications.

Reboot the device.

Reset the device to factory defaults.

Completely dry any device that gets wet.

Make sure the device is at room temperature.

Call the service provider or manufacturer, or check their website for additional information.

An LCD laptop uses technology that requires AC, which cannot be supplied by battery power. For this reason, an LCD display needs an inverter. This is required to convert DC to the AC needed.

If an inverter goes bad or is damaged, the screen goes dark. To determine whether the laptop screen is the issue, connect the laptop to an external monitor. If the monitor now works, you have solved the problem. To test whether the backlight has failed, use a flashlight and shine it directly at the screen. If the operating system is viewable, the display is getting the video signal and the problem is the inverter or the backlight. If it is the connecting cable, nothing will show on the screen. Figure 15-1 shows how the antennas and inverters are installed around the edges of the screen.

A laptop also usually has multiple video connections to be used with external monitors or overhead projectors. These connections can include video graphics array (VGA), digital visual transfer (DVI), and high-definition multimedia interface (HDMI) connectors. These can be enabled by using an extra Fn key to switch between video options. Checking whether this option has been set to external rather than the internal display should be a first troubleshooting step.

If connecting to an external monitor does not fix a display, ensure that the cable is connected firmly to the correct external port and that the external monitor is plugged in and turned on. Make certain that the correct Fn key sequence has been pressed. Try rebooting if necessary.

For problems such as a dim display, brightness can be adjusted using the correct Fn key sequence. Laptops do not usually come with contrast controls, so adjusting the brightness control may be the only option, besides replacing components.

Active-matrix screens, both LED and LCD, are set to run at a default resolution. Resolution is the number of pixels that can be displayed on the screen. Changing the resolution from the default recommended setting can cause fuzzy pictures, and setting a higher refresh rate can cause flickering on the display. If adjusting the settings does not help, updating the drivers might help. If all else fails, replacing the laptop with one that has a larger display may be the only realistic solution.

A nonresponsive touchscreen on a mobile device can be caused by simple dirt. The first thing to try is to clean the touchscreen. Fingerprints, dirt, food, and other items can block the tracking of finger movements. It also can be caused by breaking an internal connection. If the unit falls into water or is submerged, it can cause shorts or other problems. It also could be the result of a configuration setting or accidentally selecting a control option. If the screen has a crack or has been physically damaged, it will need to be replaced.

Figure 15-2 shows a Bluetooth device that has been enabled. Notice the discoverable setting is also turned on.

Is the device within the range of the wireless network?

Was the correct SSID entered along with the correct user ID and password?

Does your laptop have a Wi-Fi button, and is it turned on?

Does the device support the encryption protocol being used?

Is Wi-Fi tethering or Internet pass-through conflicting with the wireless connection?

Try rebooting the mobile device or the Wi-Fi connection. You can try removing the Wi-Fi network to which you are connecting and then try adding it again. Because this is a network connection, regular network troubleshooting methods can be employed, such as the following:

Check whether there is a proxy server configuration.

Check the IP address settings if using static addresses.

Try ipconfig /release or ipconfig /renew for a DHCP connection.

Check the Wi-Fi sleep policy.

Check that the best Wi-Fi performance setting is turned on for connecting to a distant network.

Figure 15-3 shows typical Wi-Fi settings on a mobile device.

Some laptops include a mini-PCIe wireless card that can be replaced when it fails. Laptops contain mini-PCIe slots, so inserting a regular-sized PCIe card is not possible. The most important part of any wireless card is its antenna. It can be connected to the card or the motherboard. It is important to make sure it has been disconnected and reconnected in the same manner if the wireless card is replaced.

Replacing an antenna is where using a plastic wedge tool becomes important. Sometimes the access panels can stick after removing the screws. Use the wedge to pry the plastic laptop components apart without damaging them.

Typical Windows utilities can be used to troubleshoot a hard drive problem. The best solution is to replace any hard drive that is having problems. Remember that most portable devices hold hidden recovery partitions that will need to be dealt with before replacing the hard drive.

Sticking keys may require the replacement of the entire keyboard; depending on the unit, a single key can be removed and replaced. In some cases, cleaning or using forced air can unstick a key. Remove the key by popping it up so the underside can be cleaned. Unfortunately, many laptops have keys embedded into the keyboard, so repairing or cleaning is not an option. The BIOS often reports a 3xx error with a two-digit hexadecimal code that identifies which key is stuck.

Touchpads that take the place of a mouse can go bad, or the drivers can become corrupted. A dirty touchpad can cause movement on the touchpad to become slow and choppy and cause pointer drift or a ghost cursor to appear.

Newer touchpads have added gesture features such as two- or three-finger scrolling, pinching, rotating, and swiping. Disabling these features can clear up problems. Problems also can be caused by accidentally touching the touchpad while typing.

Sometimes loading the latest driver can eliminate problems. If you have to replace a broken or worn-out touchpad, you usually have to remove the keyboard. Replace it with a similar model, being careful to reconnect all ribbon cables.

Connections from the laptop to the outlet.

The outlet is good.

Damage to any of the power components.

Connections to the AC adapter.

The DC jack on the laptop is not loose or damaged.

The correct power adapter is being used.

The battery is installed.

The battery is fully charged.

The battery is inserted properly.

The battery is still working.

The battery is not swollen due to age, overcharging, or defect.

Standby, sleep/suspend, or hibernate has been enabled and is having issues.

When a battery won’t hold a charge, check for a faulty DC jack, a faulty AC adapter, or a loose connection with an AC adapter. One of the first things to note is whether the DC jack’s LED light is lit. An AC adapter also can have an LED that can be checked. This is a great example of following the rule that it is better to check the easy items first, such as an LED light, before getting too far into the troubleshooting process.

Remember that laptops and other mobile devices have a limit on the number of hours they can run on battery power. If the battery cannot hold its charge, it might be nearing the end of its lifecycle. Batteries periodically need to be replaced. Old batteries should be recycled or disposed of in accordance with local regulations.

When a laptop or mobile device freezes, the problem can be physical or could be software. Laptops can freeze when overheated and should always be put on a flat surface. Dust build-up or lack of airflow can cause temperatures to rise. Another way a laptop or mobile device can freeze up is through insufficient memory. This can cause slowdowns in performance, stuttering, and even blue screens.

Diagnosing RAM problems can be difficult, mainly because the symptoms are not always consistent. Faulty RAM can cause your laptop to gradually deteriorate in performance and speed. Look for random restarts or for it to freeze sporadically during memory-intensive operations. Blue-screen errors and programs and files not behaving correctly can all be signs of faulty RAM. If the laptop beeps when you turn it on, it could be an indication that the RAM needs replacing. Check the BIOS manufacturer for instructions on the meaning of the beeps.

The easiest way to determine whether a stick of RAM is bad is to replace it with a known good stick. If there are more than one stick of RAM, remove one at a time and test the results. In addition, diagnostic programs can help determine whether the RAM is faulty. Because the cost is reasonable, replacing a suspect RAM stick is a good solution.

Lack of sound can be caused by volume settings you can adjust using the Sound applet in the Control Panel. Some laptops come with sound cards that have their own software a user can use to change settings. Another item to check is to confirm that the correct source is selected to play sound.

Linux machines have a sound applet that can be used to configure speakers and other input/output devices. In Mac OS X, you can check your Sound System Preference pane for configuration and diagnosing a sound problem. After you have eliminated the OS as a source of the problem, consider replacing the device.

Software problems can be caused by the OS, BIOS/UEFI issues, viruses, malware, or an installed application. Try to shut down the problematic application. Then use Ctrl+Alt+Del, go to the Task Manager, and terminate the program or service. If that fails, reboot the system.

When a mobile device app is not loading properly, determine whether the application is written for the version of the OS being used and whether the device has the resources needed to run the application. Slow performance can be caused by a storage device being almost filled up or too many applications running at the same time. Many devices come with small system applets used to determine CPU, memory, and disk utilization, which can help to determine what is causing the problem.

E-mail applications have their own set of problems depending on the type of e-mail system to which it is connecting. Web-based email systems are housed on a remote server and require nothing more than a browser to access. Client applications installed on the device, such as Microsoft’s Outlook program, connect to a server. E-mail is downloaded to the device and does not remain on the remote server.

Many support issues with e-mail systems can be caused by users forgetting their user ID or password or not remembering the SMTP/IMAP/POP3 settings. Most people do not encrypt their e-mail, even though it provides an additional layer of security. Encrypting e-mail requires setting up public and private keys; this can be a very daunting task for the average user. To troubleshoot a problem with e-mail encryption, check that both the sender and receiver are using the correct keys.

Tiny screws and small parts are a challenging reality when working on laptops. When removing small screws and multiple cables, things easily can get lost, and remembering where everything goes can be difficult. You can avoid reassembly problems by documenting and labeling all the components as you remove them. Use a piece of paper to describe the component removed and tape to hold the screws or small parts that go with it. Another way to keep track of things is to take a digital photo and document the process.

Many ribbons exist in a laptop, and they are not easy to remove. The connectors can be exposed on one side, they can snap in, or they can have spring-loaded mechanisms. Utilizing the correct tools and following the manufacturer’s documentation can go a long way toward making repair a simple process.

Several tools are available to use when cleaning a printer. Note: Be sure to unplug power to the printer before cleaning. You can use any of the following:

Compressed air

Computer (anti-static) vacuum

Isopropyl alcohol

Lint free cloth

Cotton swabs

Small brushes

Other tools are available to use when working with printers. Consider keeping the following in your toolkit: an extension magnet, screwdrivers, and small tweezers for removing paper debris. Also consider using toner vacuums or compressed air, long-handled cotton swabs, denatured alcohol, and lint-free cloths to deal with ink and toner spills.

A print queue will go offline when the printer is offline or has stopped printing. If the print queue does not restart automatically, it can be manually started under the Services applet. To access the print queue, open the Printer icon, select print queue, open the Printer menu, and check the settings. Sometimes print queues need to be cleared for a variety of reasons or a job needs to be deleted. Open the print queue, right-click the Printer, and work with the print jobs.

Check that the printer is turned on and all connections are tight and correct. You should hear the page feed mechanism make a noise, and the printer should have panel lights that come on.

For USB attached printers, many times it is important that you install the printer driver before attaching the printer. This is especially true with USB connected printers. Also make sure you have it plugged into a USB port and not a USB hub.

For networked printers, use network troubleshooting methods including checking the network cable, the protocol configuration, and any shared or authorization settings.

Replacing—Inserting a new ink cartridge or ribbon can solve many problems with printouts. Replacing worn-out parts is another method that can lengthen the service life of a printer.

Updating—Updating printer drivers can provide new features and fix problems with drivers that have become corrupted. Upgrading the paper quality used also can be a factor in maintenance.

Environment—Printers generate heat; ensure that the temperature and humidity are kept at an acceptable level. Ink and paper should be kept in cool, low-humidity, dust-free environments.

Static eliminator strips need to be changed when paper starts sticking before being ejected, more than one sheet of paper is being pulled through at a time, or the paper is being crumpled. If the ink smears on a printout from a laser printer, check the fuser assembly.

Replaceable parts include the fuser assembly, transfer rollers, separation pads, and pickup rollers. Installing a printer maintenance kit will replace these items. A maintenance kit should be installed when a Perform Maintenance message is displayed on the printer LCD screen. A maintenance kit usually consists of a fuser, which heats and bonds the toner to the paper, a transfer roller, which transfers toner from the cartridge to the paper, and various rollers and separation pads. All the components that reside in the printer cartridge itself, such as the drum, primary corona, cleaner blade, and toner, can be replaced when a new toner cartridge is placed in the machine.

To clean a laser printer, you can use forced air or a lint-free cloth to remove paper dust from the inside of the unit. You also can clean the corona wire using rubbing alcohol on a cotton swab. It is not recommended to clean anything within the toner cartridge itself.

Inkjet manufacturers usually include maintenance and diagnostic utilities with their drivers that provide services that include some of the following:

Clean the print heads.

Adjust printing alignment by calibrating the printer.

Clean ink cartridges.

Perform diagnostics.

Many printers also give you an estimate on how much ink is left in each cartridge, information about paper conditions, and errors during the printing process. Figure 15-4 shows a typical inkjet printer set of utilities that include the functions listed previously.

The cleaning utilities found in the print driver are designed to work with the ink cartridges. They do not clean the printer itself. To clean an inkjet printer, first remove the cartridges; then use a paper towel or a cotton swab dipped in rubbing alcohol and wipe it along the back or underside of the ink cartridge holders. You also can use forced air or lint-free cloths to clean out paper dust. Working with printers eventually requires dealing with paper jams. Try to avoid pulling stuck paper out from under the front cover to avoid damaging the printer. It is better if it is pulled from the back of the printer. Remove any loose paper from the tray and then start removing one sheet of stuck paper at a time. After you have removed the paper jam, reload the printer and perform a test page.

It is important to keep the heating element clean. Some thermal printers have a thermal printer cleaning pin. Direct thermal printers have ribbons with built-in printhead cleaners. Because the print head is a delicate part of the thermal printer, it eventually will need to be replaced.