Laptops make all manner of noises, from beeps to whirs to hums. Your laptop's AC adapter, however, typically does its job of providing constant electricity silently. A ticking or clicking noise emanating from your charging adapter indicates a problem with the cord, which could spell trouble for your laptop. A faulty adapter could provide your laptop with too much or too little electricity, resulting in short circuits and improper charging.
A failing or malfunctioning adapter charger issues strange noises -- any noise emitted by your charger is unusual -- when plugged in. The battery may not charge properly when the adapter is plugged in, or the laptop may not register the presence of the adapter cord at all. The charging icon in the status bar of your desktop may not appear, or it may show more or less of a charge than your battery actually holds.
Measure Voltage Output
A failing adapter will not deliver the amount of electricity your laptop requires to function properly. In some cases, the adapter can cause short circuits by delivering too much power. Check the voltage output of your adapter with a voltmeter and compare the readings to the amount listed on the adapter's brick. Small fluctuations higher or lower than the listed amount are normal, but if the reading varies too much on one side or the other, the cord is faulty and needs to be replaced.
Depending on the age and warranty status of your adapter, you may want to contact your laptop manufacturer for a replacement charger. If the adapter is out of warranty, you can order a new cord from your manufacturer or find a third-party replacement online or at a brick-and-mortar store. When looking for a new adapter, the connector end -- the end that plugs into the laptop -- must match the laptop's port perfectly. Most retail websites will list what laptops and adapters third-party cords are compatible with to help eliminate the possibility of purchasing the wrong replacement.
Your laptop requires only a fraction of the electricity provided by your home's wall outlet; the adapter cord converts the energy for safe laptop use. Printed on a label on the underside of your laptop is the specified voltage (V) and amperage (A) that your laptop needs. Multiply these two numbers together to get the proper number of watts (W) you should look for in an adapter. A laptop that requires 15V and 3A, for example, would need an adapter that provides at least 45W. Higher wattage adapters are fine -- a 60W or 75W adapter would work for the example -- as the laptop will accept only the amount of electricity it needs. Lower wattage adapters are not powerful enough and could damage the laptop.