Laptop won't charge: the four faults behind it, in the order to check them
A laptop that will not charge is one symptom with four very different causes, and the cost ranges from a cable to a board-level repair. The order you check them in is what saves money.
A swollen battery
is a safety issue, not an inconvenience. Stop charging it, stop pressing the case closed, and get it looked at.
- The $49 diagnostic comes off the bill if you go ahead with the repair.
- Port and charging-circuit repairs are quoted after diagnosis, before any work starts.
- Battery replacements are quoted per model, and the old battery is returned to you.
One symptom, four faults
A laptop needs four things to charge: a power supply delivering the right voltage and current, a port that connects it to the board, a battery that accepts a charge, and a charging circuit on the board that regulates it. Any one of them failing produces the same complaint, and the difference in repair cost between the cheapest and the most expensive cause is large.
- The charger or cable: damaged, wrong wattage, or a USB-C supply that never negotiated the power the laptop needs.
- The port or jack: worn barrel jack, bent USB-C pins, or cracked solder joints where the port meets the board.
- The battery: worn past the point of holding charge, or a cell that has failed and reads as not present.
- The charging circuit: a charging IC or fuse on the board, which usually means the machine runs on AC but never charges.
Check these before you pay anyone
Ten minutes of your own checks rules out the cheapest causes and gives a technician a much better starting point.
- Try a different outlet and, if you have one, a known-good charger of the same voltage and connector. A wrong-wattage supply is the most common cause of 'it charges slowly or not at all'.
- For USB-C machines, check the charger's wattage. A phone charger will power a laptop, and often will not charge it.
- Wiggle the plug gently while watching the charging light. If the light flickers, the port or the jack is the fault.
- Hold the power button for fifteen seconds with the charger connected, then try again. Some machines latch up rather than fail.
- On Windows, generate a battery report with powercfg /batteryreport and read the design capacity against the full-charge capacity. A health figure well under 80 percent points at the battery.
- Look for a bulge: a trackpad that sits proud, a case gap near the front edge, or a lid that no longer closes flat.
Why timing matters
Stop using and stop charging a laptop with a swollen battery. Do not press the case shut, and do not leave it on a charger overnight. Bring it in.
The port and the jack
Barrel jacks wear from being plugged in at an angle, and the solder joints that hold them to the board crack long before the jack itself fails. That is why a laptop often charges only when the plug is held at the right angle: the joint is making intermittent contact. Replacing the jack and reflowing its joints is a contained repair on most machines.
USB-C ports fail differently. The pins bend, lint packs into the back of the port, or the port's controller gives up. A port that works for data but not for charging, or vice versa, is almost always the port or its controller rather than the battery.
The battery
Batteries are consumables. Three or four years of daily charging is a normal life, and a worn battery drags the whole machine with it: sudden shutdowns at 30 percent, reduced performance on battery, and heat that ages everything around it.
The replacement itself is straightforward once the right part for the exact model is in hand, and the old battery goes back to you rather than into a bin, because a swollen cell needs proper disposal.
When the board is the fault
If the machine runs perfectly on the charger but the battery percentage never moves, or the charger is recognised but no current flows, the fault is usually in the charging circuit on the board. Some of these are a fuse or a single component and are worth repairing. Others sit under a shield on a dense board and are not.
That is the point of the diagnostic: it produces a number and an honest recommendation, including the recommendation that a machine is not worth the board-level work. You still get the diagnosis, and you decide with the price in front of you.
What it costs
Diagnosis is $49 and is waived when you proceed. Batteries and charging port assemblies are quoted per model before ordering, and board-level charging faults are quoted once the fault is confirmed.
Why MTech Repair
A repair bench, not a mall kiosk.
Diagnostics happen in front of you, parts grades are named before they are ordered, and every device leaves with a tested result rather than a promise.
- Quote first
- You approve the exact price before a single screw comes out.
- 90-day warranty
- Workmanship is covered, on both local and mail-in repairs.
- Same-day bench
- Most phone repairs are finished while you wait, 45 to 60 minutes.
- Tracked both ways
- Mail-in repairs ship insured and tracked in both directions.
Common questions
What people ask before booking this repair
Get it fixed
Two ways to hand it over, one standard of work.
Drop off or meet up around Flemington for same-day service, or mail the device in from anywhere in the US. Computers are tested before and after, and you hear from a technician, not a call center.
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