If you are having problems with the backlight on your Xiaomi Redmi Note 9, you can do the following:
Check Backlight:
- Use a backlight or small flashlight to check if it is lit.
- If the light does not come on, there may be a problem with the backlight module or related components.
Check Components:
- Check components such as backlight, mounting components and cables for signs of damage.
- Make sure there are no oxidized or cracked components.
Check Cables:
- Check the component cables to ensure there are no broken or damaged wires.
- If a problem is detected, the cable may need to be replaced.
Voltage Test:
- Use a power meter to check voltage at key points on the circuit.
- Check if there is a correct voltage difference.
Check Circuit Diagram:
- If you have the circuit diagram of your Xiaomi Redmi Note 9, check the diagram to identify the important components and their locations on the board.
If you are not confident about repairing it yourself, take your phone to an official Xiaomi service center or contact a mobile phone repair expert for assistance. Note that self-repair may void your warranty, so consider carefully before doing so.