If you service MediaTek devices, you have run into chipsets listed twice — once as V4 and once as V5. This confuses a lot of technicians, because the model lists under each look identical. Here is what the difference actually is and why it matters before you start any operation.
V4 and V5 are firmware revisions, not phone models
The V4 and V5 labels describe the security revision of the device firmware and preloader, not a different handset. A Redmi 13C sold in 2023 and the same Redmi 13C sold in 2024 can carry different revisions. That is why our MT6789 V4 and MT6789 V5 lists contain the same devices — the phone is the same, the security state is not.
Roughly, V4 corresponds to the 2023 security baseline and V5 to the 2024 baseline. MediaTek tightened preloader and download-mode protections between them, which changes what a servicing tool has to do.
Why the model name will mislead you
Manufacturers ship the same commercial model across regions and production runs with different firmware. Two units with identical model numbers on the box can behave completely differently on the bench. If you pick an operation based on the model name alone, you can end up with a failed or partial operation on a device that was perfectly serviceable using the correct profile.
This is the single most common cause of avoidable failures we see in support tickets.
How to identify the revision correctly
Read the revision from the device itself before you begin:
- Check the firmware build and security patch level reported by the device, not the retail model number.
- Analyse the preloader — the preloader carries the security metadata that determines which profile applies.
- Where the device boots normally, the Android security patch date is a strong indicator of the baseline in use.
- If the device has been reflashed by a previous repair, treat the current firmware as authoritative, not the original spec.
Which chipsets this applies to
On our MediaTek support list, the split currently applies to MT6789 (Helio G99 family) and MT6855 (Dimensity 930). Other MediaTek chipsets are listed once because the distinction does not change the operation.
If you are not sure
Do not guess. Identify the revision first, and if the device is still ambiguous, open a support ticket with the firmware details and we will tell you which profile applies. Checking takes a minute; a failed operation costs a lot more.
See the full MediaTek supported model list.