Troubleshooting Hardware Issues Lesson 001: Power Issues Part 1

What is the first possible issue that a tech should look at when troubleshooting a computer?

If it gets proper power.

What are the main causes of power issues?

Power button is not connected properly to the motherboard, wall outlet is faulty, power cable to the computer is faulty, power supply is faulty, power cables from power supply components are faulty, incorrect voltage settings on PSU.

Why would a power button not be connected to the motherboard?

The wire became disconnected.

What happens when the power button is not connected to the motherboard?

The motherboard cannot receive the signal to tell the system to turn on.

How does a tech verify if the power issue is because of an improper connection of the power button to the motherboard?

Disconnect from power, open the system casing, and verify if it’s properly connected and seated.

What does it mean if the power issue is caused by a faulty wall outlet?

That the computer isn’t getting adequate power from the building, to the computer.

How does a tech verify if the power issue is because of a faulty wall outlet?

Through the use of a multimeter or voltmeter to verify proper voltage and hertz cycle.

What is a hertz cycle?

The amount of cycles per second an AC completes.

What is the volt and hertz cycle used in the U.S. and Canada?

110-120 and 60.

What is the volt and hertz cycle used in Europe or Asia?

220-240 and 50.

How does a tech check if the power issue is caused by a faulty power cable?

Disconnect it at both ends, and use a multimeter to run a resistance check across it.

How does a tech use a multimeter to check for a faulty power cable to verify full continuity?

Place one of the leads on one of the prongs and the other lead into the hole on the other side.

How many times does a tech need to run a resistance check on a possible faulty power cable and why?

Three separate times for each of the pins on the cable.

What is considered a normal resistance reading when checking if a power cable is faulty using a multimeter?

0 ohms.

When using a multimeter, what kind of resistance reading is considered an indicator of a faulty power cable?

Infinite ohms, or a very high number of ohms.

What should be done if it is verified that the power issue is caused by a faulty power cable?

Replace it.

What are the three levels of DC voltage that a PSU needs to provide?

12, 5, 3.3.