Direct answer
For the Samsung Galaxy S23, power source, cable/adapter, port debris/liquid, temperature and battery protection should be separated. First, test two known-good specified cables/adapters and a wall outlet.
What this covers
- Samsung Galaxy S23 (SM-S911*)
- Samsung Galaxy family; S Pen, foldable display, DeX, USB moisture and One UI features vary by exact model.
- The specific fault this record addresses: will not charge or charges slowly
What it does not cover
- ×The same symptom on a different Samsung product line, which has its own record and its own cited source
- ×An on-screen error code whose meaning has not been checked against this exact model's manual
- ×Live electrical, gas, sealed-system, internal battery-cell or structural repair — a technician boundary, not a self-service step
Differential
What actually causes this, and how to tell them apart
These are ordered by how often each one is the answer, not by how easy it is to try. The point of the middle column is that two causes producing the same headline symptom rarely produce the same detail — that detail is what tells you which one you have before you change anything.
- 1
Lint compacted in the charging port
What separates it The cable feels like it seats but wobbles, or only charges at one angle, or has become progressively worse over months in a pocket. This is the single most common cause of a phone that will not charge and it is almost always mistaken for a failing port.
How to confirm Look into the port with a bright light. Compacted lint looks like a flat floor part-way down; a clean port shows the contacts at full depth. It is compressed by every insertion, so it accumulates invisibly.
- 2
The cable, not the phone
What separates it Charging works with a different cable, or works when the cable is held at an angle. Cables fail internally at the strain point near either connector, and a cable that still transfers data can be inadequate for current.
How to confirm Swap one variable at a time: same adapter and port, different cable. This is the fastest and cheapest test available and it resolves a large share of these.
- 3
The adapter is underpowered for the phone
What separates it It charges, but very slowly, or only while the screen is off. A low-output adapter, a computer USB port or an old car charger supplies far less than a modern phone expects.
How to confirm Compare the adapter's output rating against the phone's supported charging speed. Slow charging with a known-good cable is nearly always this.
- 4
The phone is refusing to charge on temperature
What separates it It stops charging in a hot car or outdoors in winter, and resumes indoors. Both major platforms suspend charging outside a safe temperature band and do not always say so.
How to confirm Bring it to room temperature and retry before anything else. A phone that charges indoors and not in the car has told you the answer.
- 5
Moisture detected in the port
What separates it An explicit moisture or liquid warning, or silent refusal after swimming, rain or a humid bathroom. The detection is deliberately conservative and can persist after the port feels dry.
How to confirm Leave it unplugged, port down, in moving air for several hours. Do not use heat and do not put it in rice — heat drives moisture further in and rice leaves dust in the port.
- 6
A USB-C cable that carries data but not enough current
What separates it It charges, very slowly, on a cable that works perfectly for transferring files. USB-C carries several power profiles and a cable built for data is not necessarily rated for charging current.
How to confirm Swap for the cable supplied with the phone, or one explicitly rated for its charging speed. This is specific to USB-C and does not arise on the Lightning models.
- 7
The wireless charger is misaligned or blocked by the case
What separates it It charges on a cable and not on the pad, or charges intermittently on the pad. Wireless coil alignment is tight, and a thick case, a metal plate or a card in the case defeats it.
How to confirm Remove the case and centre the phone on the pad. Working without the case is the finding.
- 8
A deeply discharged battery needs time before it responds
What separates it A phone left flat for days shows nothing at all when plugged in, and people conclude it is dead. Deep discharge requires a trickle period before the phone can display anything.
How to confirm Leave it on a known-good charger for at least half an hour before judging. This one costs nothing but patience and recovers a real number of phones.
- 9
The port is physically damaged or the pins are bent
What separates it The cable is loose in the port, or the phone charges only under pressure. This is what people assume first and what it usually is not — check lint before concluding damage.
How to confirm Compare the feel against a known-good phone of the same model. A genuinely damaged port is loose in every orientation with every cable.
- 10
Software has stopped negotiating charge
What separates it It charges when powered off but not when running, or the charge indicator behaves erratically. Charge negotiation is software as well as hardware.
How to confirm Force-restart the phone with the charger connected. This is safe, fast and occasionally the whole answer.
Before you touch a setting
Record this first — changing settings destroys the evidence
Every item below stops existing the moment a reset, re-pair or settings change is made. Written down first, they are what separates the causes above; recovered afterwards, they are guesswork.
- Which combinations were tried — this adapter with that cable, in that outlet — rather than a general statement that several were tried. The pattern across combinations is the diagnosis.
- Whether the phone shows any charging indication at all, including on a black screen, and whether it responds to a force-restart while connected.
- Whether it charges when powered off but not when running.
- The ambient temperature, and whether it has been in a hot car or outdoors in the cold.
- What the inside of the port looks like under a bright light — contacts visible at full depth, or a flat floor of compacted lint part-way down.
- The adapter's output rating, read from the adapter itself.
- Whether a moisture or liquid warning has appeared, and when the phone was last near water.
- Whether it charges on a cable but not on a wireless pad, and whether the case was on.
Look inside the port with a bright light
ReversibleCompacted lint is the most common cause of a phone that will not charge, and it is compressed further by every insertion, so it builds up invisibly over months. A clean port shows the contacts at full depth; a blocked one shows a flat floor part-way down. This costs ten seconds and settles a large share of cases.
Change exactly one variable at a time
ReversibleSame adapter and outlet, different cable. Then same cable, different adapter. Trying several things at once produces a result you cannot attribute, and cables are the second most common failure after lint.
Leave a flat phone on a known-good charger for half an hour
ReversibleA deeply discharged battery cannot display anything until it has trickled for a while. Judging a phone dead after two minutes on the charger is a genuine and common mistake, and it costs nothing to avoid.
Bring it to room temperature and retry
ReversibleBoth major platforms suspend charging outside a safe temperature band, and they do not always say so. A phone that will not charge in a hot car or outdoors in winter, and does indoors, has already given you the answer.
Clear the port with the correct method only
ReversibleA wooden or plastic toothpick, gently, with the phone powered off. Never a metal pin, never compressed air forced into the port, and never a liquid. The contacts are fragile and repairing them costs far more than the lint ever did.
Dry a moisture warning properly
ReversibleUnplugged, port facing down, in moving air, for several hours. Not heat — that drives moisture further in — and not rice, which leaves dust exactly where you least want it. The detection is deliberately conservative and clears on its own once dry.
Test wireless charging without the case
ReversibleCoil alignment is tighter than it looks, and a thick case, a metal plate or a card defeats it entirely. Charging without the case centred on the pad is the test, and it distinguishes a charger problem from a phone one.
Force-restart with the charger connected
ReversibleCharge negotiation is software as well as hardware, and a phone that charges when powered off but not when running is describing that. This is safe and fast and is occasionally the entire answer.
Compare the adapter's rating against what the phone supports
ReversibleA low-output adapter, a computer USB port or an old car charger will charge slowly or only with the screen off. Slow charging on a known-good cable is nearly always the adapter rather than the battery.
Model-specific
What is true of this model and not of its siblings
Generic advice for the product line fails here. Each item below is a property of this specific model family that changes which of the steps above apply to you.
- Model scope
- SM-S911*. Samsung Galaxy family; S Pen, foldable display, DeX, USB moisture and One UI features vary by exact model.
- Tier — flagship base (no S Pen)
- The compact flagship — no S Pen, smaller battery than the Plus/Ultra. One UI over Android, long updates, DeX.
- eSIM + physical SIM, IP68
- eSIM and physical SIM, IP68, fast + wireless charging.
- Size trade-off
- Its smaller battery drains faster under heavy use than the larger models — size, not a fault.
- Connector
- USB-C. A cable that fits is not necessarily a cable rated for this phone's charging speed — USB-C carries several power profiles and a cable built for data will charge slowly or intermittently while seating perfectly.
- Biometric
- An in-display fingerprint reader, which looks through the screen. A thick or incompatible screen protector genuinely interferes with it, which is why unlock reliability often changes the day a protector is fitted rather than gradually.
- SIM
- Carries an eSIM. An eSIM does not travel with the handset the way a plastic SIM does: a phone swap, a factory reset or a repair can leave the profile behind, and restoring it is a carrier action rather than a phone setting.
- SIM
- Supports two active lines. The default line for calls, for messages and for cellular data are three separate settings, and getting them crossed produces calls arriving on one number while data or messages use another — with almost no indication that anything is wrong.
- Modem
- 5G capable. In marginal 5G coverage the phone hands repeatedly between 5G and LTE, which costs more battery and generates more heat than settling on either — so the preferred-network setting is a real diagnostic lever rather than a preference.
- Charging
- Supports wireless charging. Coil alignment is tighter than it looks and a thick case, a metal plate or a card in the case defeats it entirely — so wireless charging failing while cable charging works is usually the case rather than the phone.
- Water resistance
- Rated water resistant, which is not waterproof and which degrades with age, drops and seal disturbance. The rating covers incidental exposure; it is not a guarantee, and moisture-detection warnings are deliberately conservative and can persist after the port feels dry.
- Platform
- Android, with a manufacturer interface layer over it. Battery optimisation and background-execution restrictions are applied per app and are far more aggressive than on iOS — which is why 'set this app to unrestricted' is a real fix here and has no equivalent elsewhere.
- Symptom boundary
- This record covers Samsung Galaxy S23 when it will not charge or charges slowly. A different symptom on the same hardware, or this symptom on a different Samsung product line, has its own record with its own causes and its own cited source.
Stop boundary
When this stops being a self-service repair
Continuing past any one of these costs more than the repair saves — in safety, in warranty, or in evidence a technician needs.
- !The battery is swollen, the back or screen is lifting, or the phone is hot while idle. Stop charging it and do not compress or puncture it.
- !The port is visibly damaged, the pins are bent, or the cable is loose in every orientation with every cable — that is a repair, and probing further risks the board.
- !There is corrosion or residue in the port after liquid exposure, which does not clear by drying.
- !The phone charges only under physical pressure on the connector, which is a failing port and will fail completely.
Evidence ledger
Sources behind this answer
Visible sources support the visible claims. Home Product Support records the publisher, the fact used and the review date; community reports can suggest an issue but do not become a published fact on their own.
Where the manufacturer's article stops. Samsung publishes this as "Samsung phone or tablet will not charge". Covers a Galaxy phone that will not charge or charges slowly - cable, adapter, port debris and moisture, and safe-mode checks. Probed 2026-08-21: title-verified. What that article does not carry is the model boundary — it is written for a product line, and SM-S911* is the scope applied here. Where a control label, terminal, indicator pattern or reset sequence differs on your unit, the manual for that exact model is the authority, not this page and not the article.
Exact questions
Common follow-ups
My Galaxy S23 gets warm and drops battery fast when gaming.+
That is normal under load — gaming, 5G, high brightness and 120 Hz all generate heat and drain any compact flagship quickly, and the S23's smaller battery shows it sooner than a Plus/Ultra. Avoid charging while gaming (it adds heat), lower the refresh rate or resolution for long sessions, and let it cool. If it is hot at idle, look for a misbehaving app in Settings › Battery and restart the phone.
Can I use any USB-C cable?+
Any will fit, which is exactly the trap. USB-C carries several power profiles, and a cable built for data transfer is not necessarily rated for this phone’s charging current — it will charge slowly or intermittently while seating perfectly. Use the supplied cable or one explicitly rated for the phone’s charging speed.
My phone stopped charging. What should I check first?+
The port, with a bright light. Compacted lint is the most common cause by a wide margin — every insertion presses it further in, so it accumulates invisibly over months and then presents suddenly as a port that will not hold a cable. A clean port shows the contacts at full depth.
How do I clean the charging port safely?+
Phone off, a wooden or plastic toothpick, gently, working the debris out rather than pushing it in. Never a metal pin — the contacts are fragile and bridging them is worse than the lint. Not compressed air forced into the port, and nothing liquid.
It only charges if I hold the cable at an angle.+
That is nearly always the cable failing internally at the strain point, or lint holding the connector off its full seat. Both are cheap to rule out: swap the cable first, then inspect the port. A genuinely damaged port is loose in every orientation with every cable.
The phone is completely dead and shows nothing when plugged in.+
Leave it on a known-good charger for at least half an hour before concluding anything. A deeply discharged battery has to trickle for a while before the phone can display anything at all, and judging it dead after two minutes is a common and expensive mistake.
Why does it stop charging in the car?+
Temperature. Both major platforms suspend charging outside a safe band and do not always tell you they have. A phone in a sunlit car, or outdoors in a hard frost, is outside that band — bring it to room temperature and it will resume.
I got a moisture warning but the port is dry.+
The detection is deliberately conservative and can persist after the port feels dry to you. Leave it unplugged, port down, in moving air for several hours. Do not apply heat, which drives moisture inward, and do not use rice, which leaves dust in the port.
It charges slowly even with a good cable.+
Check the adapter's output rating against what the phone supports. A low-output adapter, a laptop USB port or an older car charger supplies a fraction of what a modern phone expects, and the symptom is exactly this — it charges, just barely, and better with the screen off.
Wireless charging stopped working but the cable is fine.+
Take the case off and centre the phone on the pad. Coil alignment is tighter than it looks, and a thick case, a metal plate or a card in the case defeats it entirely. Working without the case is the finding.
Is it worth buying a more powerful charger?+
Only after the cable and the port are excluded. A faster adapter cannot help a phone whose port is packed with lint or whose cable has failed internally, and those two account for most of these faults. Test the cheap things first.
It charges when switched off but not when it is on.+
That points at software rather than the hardware path — charge negotiation is software too. A force-restart with the charger connected is safe, fast, and is occasionally the entire fix.
Should I use the charger that came with the phone?+
Use one that meets the phone's specification, whether or not it is the original. What causes trouble is the opposite end of the range: very old adapters, unbranded ones with no stated output, and computer ports — all of which supply less than the phone expects.
The back of the phone has started to lift.+
Stop charging it immediately. A lifting back or screen means the battery is swelling, which is a stop condition regardless of how well the phone otherwise works. Do not compress it, do not puncture it, and do not leave it charging unattended.
Does this answer apply to every Samsung model?+
No. It is scoped to SM-S911*. Samsung Galaxy family; S Pen, foldable display, DeX, USB moisture and One UI features vary by exact model.
What should I record before troubleshooting not charging or slow charge?+
Record the complete model identifier, exact message or indicator, software/firmware where visible, the operating stage and what still works.
Why is a factory reset not the first step?+
A reset can erase accounts, networks, maps, schedules or preferences without distinguishing not charging, slow charge. The ordered checks preserve that evidence.
When should I stop and use qualified service?+
Stop for heat, swelling, liquid, corrosion, melted insulation or bent contacts.
Answer for the exact device and software version shown above.