Common faults in electronic circuit boards and how to identify them

Practical guide to the most common faults in electronic boards and circuits: symptoms, causes and what to do before taking the device to a repair service in Buenos Aires.

·7 min read·FixBA · Buenos Aires, Argentina

Why electronic boards fail

Electronic boards are sensitive to multiple environmental factors: temperature, humidity, unstable mains voltage and component quality. In Buenos Aires and the metropolitan area, power cuts and voltage spikes are frequent causes of damage to electronics in industrial and domestic equipment.

Most common faults we repair at FixBA

These are the faults we see most frequently:

  • Swollen or burst electrolytic capacitors: cause spontaneous shutdowns, slow starts or instability.
  • Burned MOSFETs or transistors: usually caused by overload or short circuit on the load.
  • Blown fuses: usually a symptom of another fault, not the root cause.
  • Interrupted PCB tracks due to overheating or mechanical damage.
  • Moisture or liquid corrosion: affects conductivity of components and tracks.
  • Microcontrollers damaged by static or incorrect voltage.
  • Transformers with a shorted turn: detected by abnormal temperature or noise.

Symptoms that indicate an electronic fault

These symptoms suggest there is a board problem that requires diagnosis:

  • The device does not power on even though it has power.
  • It powers on but shuts off after a variable time.
  • Intermittent operation: sometimes it works, sometimes it does not.
  • Abnormal noise (hum, click, whistle from the power supply).
  • Smell of burning, even if the device continues working.
  • Incorrect or unstable output voltages.
  • Alarms or display errors appearing with no known cause.

What to do (and not do) before diagnosis

Before bringing the device to the repair service, follow these steps:

  • Disconnect the device from the supply if there is a smell of burning.
  • Do not try to clean the board with water or non-specific products.
  • Note when the problem started and what happened just before.
  • If the device shows an error code, photograph it.
  • Do not attempt repair without experience; a short circuit can damage additional components.

How we work at FixBA

We receive the board or device, carry out a technical diagnosis, identify the damaged components and present a clear quote before proceeding. We work with quality replacement components and provide a warranty on the work performed.

Frequently asked questions

Can you repair boards without technical documentation?
In most cases yes. We work with visual inspection, signal measurements and comparison with similar circuits.
What happens if the board has irreversible damage?
We report this during diagnosis. In that case we can advise you on replacement alternatives or on what data is useful to find a replacement board.
Do you work with boards from unbranded equipment?
Yes, as long as it is electronically accessible. We evaluate each case individually.

Need to repair equipment in Buenos Aires?

FixBA is an electronics repair service in Buenos Aires, Argentina. Send us photos on WhatsApp.

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