In New Zealand, low-cost chargers and cables are everywhere. The price looks good,
but inside you often find poor quality chips, weak insulation, and unstable power delivery.
We see the result in the workshop every week: phones that charge slowly, overheat, reboot,
or stop charging altogether because of bad chargers.

Customers keep asking one question:
“How do I know if my charger is genuine and safe?”
This guide gives you a clear checklist you can follow at home.

Signs Your Charger Might Be a Problem

You probably know these situations:

• The cable looks fine, but the phone keeps connecting and disconnecting.
• “Fast charging” is printed on the box, yet the phone charges very slowly.
• The phone gets hot while doing nothing except charging.
• The battery percentage jumps up and down or drains quickly after charging.

Most people blame the phone or the battery.
In many cases, the silent culprit is the charger or cable.

Some third-party chargers even copy the logo and shape of Apple or Samsung products,
but inside they use low-grade components that deliver unstable voltage and poor isolation.

Real Cases We See in the Workshop

Here are typical examples from actual repairs:

• A customer used a $10 no-name charger with a Galaxy S21.
  After some time the phone fell into a boot loop. The power management IC had taken repeated
  over-voltage spikes and eventually failed. Mainboard repair was required.
• Another customer brought in an iPhone with a blackened charging port.
  Internal insulation in the cheap charger had broken down and caused arcing.
  The charging port and related components needed replacement.

Cases like these come in every week. Once customers see the photos of the damage,
they usually switch to proper chargers on the spot.

How to Check If Your Charger Is Genuine and Safe

You can do several objective checks without opening anything.

1. Model code and branding

• Apple: Genuine Apple chargers use a clear A-xxxx model code
  (for example, A1400, A1699) printed with clean, sharp text.
• Samsung: Look for codes like EP-TA or EP-T
  on the label, again with consistent, high-quality printing.
• Blurry fonts, spelling mistakes, missing serial numbers, or random letters and numbers
  are red flags.

2. Output label and safety marks

• Check the input and output ratings on the label.
  They should be clear and consistent (e.g. 5V⎓3A, 9V⎓2.22A).
• For fast charging, genuine units specify proper USB PD or PPS profiles.
• In New Zealand, look for recognised electrical safety marks and approval numbers.
  Many unsafe imports lack these.

3. Weight and build quality

• Genuine chargers contain proper transformers, filters, and insulation,
  so they feel relatively solid for their size.
• Extremely light chargers are often missing critical components, which makes them less safe.
• Run your fingers along the edges. Rough plastic, sharp seams, or misaligned pins
  are common signs of low-quality manufacturing.

4. Charging stability and phone behaviour

• Many phones show basic charging information in the settings:
  on Samsung, check Settings > Battery and device care > Battery;
  on iPhone, watch for messages like “Not charging” or “This accessory may not be supported”.
• If you want to go deeper, you can use a USB-C power meter or PD-reader app
  (when charging via USB-C) to see how stable the voltage and current are.
• Frequent “fast charging” / “cable disconnected” pop-ups, rapid temperature rise,
  or strange battery percentage jumps are warning signs.

5. Technical standards behind genuine chargers

Genuine Apple chargers use certified controller chips (such as C48/C89 in certified cables)
and follow USB-IF Power Delivery standards.
Genuine Samsung fast chargers support PPS (Programmable Power Supply),
which finely adjusts voltage within a range like 3.3–11V to match the phone’s needs.

Many fake chargers skip these standards completely. The result is unstable voltage,
more stress on the battery, and long-term damage to power ICs on the mainboard.

Not Sure If Your Charger Is Safe?

If you are unsure about your charger, bring it together with your phone to a repair shop
that understands board-level faults, not just screen swaps.
A quick check can prevent a much more expensive mainboard or battery replacement later.

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