Software Flashing – SS2 Computer Hardware & GSM Repair Lesson Note (Second Term)

Flashing is the process of deleting a phone’s old or broken Android operating system and installing a fresh, clean version. It wipes the phone’s memory, like formatting a computer. To flash a phone, a technician needs three things: the correct firmware, the right drivers and a flashing tool that matches the phone’s chip.

Class: SS2

Subject: Computer Hardware and GSM Repair

Behavioural objectives

By the end of the lesson, students should be able to:

• explain what flashing is and when a phone may need it;
• name the three things needed before flashing a phone;
• match MediaTek (MTK), Spreadtrum (SPD) and Samsung phones to the correct flashing tool;
• list the steps for flashing a phone safely;
• state the cause and fix of common flashing errors.

What is flashing?

Have you ever had a phone that gets stuck on the “Logo” and won’t go to the home screen? Or a phone that has become very slow and keeps showing “Unfortunately, App has stopped”?

Flashing is the process of deleting the old, broken Operating System (Android) and installing a fresh, clean version. Think of it like “formatting” a computer or “re-installing” Windows. It wipes the phone’s memory and gives it a brand-new “brain.”

What three things do you need to flash a phone?

Before you can flash a phone, you need three specific things. If one is missing, the process will fail.

1. The firmware (the “OS”)

This is the actual Android software file. It is often called a Stock ROM. You must find the exact version for the specific model of the phone. For example, software for a TECNO Spark 5 Pro can damage a TECNO Spark 7.

2. The drivers (the “translator”)

When you plug a phone into a computer, the computer doesn’t naturally know how to talk to the phone’s chip. A driver is a small piece of software that tells the computer: “Hey, this is an Android phone, please listen to it.”

• Common drivers: VCOM Drivers (for MTK chips) or SPD Drivers.

3. The flashing tool (the “injector”)

This is the computer program that “pushes” the firmware into the phone.

• SP Flash Tool: used for phones with MediaTek (MTK) chips.
• SPD Upgrade Tool: used for phones with Spreadtrum (SPD) chips.
• Odin: used specifically for Samsung phones.

How do you identify the chipset (MTK vs. SPD)?

You cannot use the wrong tool for the wrong chip. Before flashing, a technician must know what “engine” is inside the phone.

• MediaTek (MTK): found in most Infinix, TECNO and older Huawei phones. We use SP Flash Tool.
• Spreadtrum (SPD): found in many “budget” or small Android phones and itel devices. We use SPD Upgrade Tool.
• Qualcomm: found in high-end phones like Samsung, Google Pixel or some Redmi models.

What are the steps for flashing a phone safely?

1. Backup: Flashing wipes EVERYTHING (photos, contacts, messages). Always tell the customer their data will be gone.
2. Charge the battery: Never flash a phone with less than 50% battery. If the phone dies in the middle of flashing, it becomes a “Brick” (a useless piece of plastic).
3. Load the scatter file: In the flashing tool, click “Choose” and find a text file called a Scatter File. This file tells the tool exactly where to put each part of the software.
4. The connection:
   1. Turn the phone completely OFF.
   2. Hold the “Volume Down” or “Volume Up” button (this is the Boot Key).
   3. Plug in the USB cable.
5. The progress bar: You will see a red bar, then a yellow/blue bar. Do not touch the cable until you see a “Success” green circle.

What are the common flashing errors and their fixes?

• “BROM Error: S_FT_DOWNLOAD_FAIL”: This usually means your USB cable is bad or the port is loose. Try a different cable.
• Phone stuck at 0%: Your drivers are not installed correctly. Re-install the VCOM drivers.
• Bootloop (still stuck on Logo): Sometimes after flashing, you need to go into “Recovery Mode” and perform a “Wipe Data/Factory Reset” to clear the old cache.

Which flashing tool and file does each phone use?

Student safety warning

Flashing is the “Last Resort.” Always try a Hard Reset (holding Volume Up + Power) first. If a Hard Reset doesn’t fix the problem, only then should you attempt to flash the phone. One wrong file can “Hard Brick” a phone, meaning it will never turn on again!

Evaluation

1. What is flashing?
2. Name the three things you need before you can flash a phone.
3. Which flashing tool is used for a phone with an MTK chip? Which is used for an SPD chip?
4. Why should a phone have at least 50% battery before flashing?
5. A phone is stuck at 0% during flashing. What is the likely cause, and what should you do?

Assignment

1. Write the five steps of the safe flashing guide in your own words.
2. Explain why flashing should be the “last resort” and say what you should try first.
3. Copy the table of flashing tools and complete it for TECNO / Infinix, itel and Samsung phones, giving the key file type for each.