Vivo Y21 5G PD2542 ISP Pinout [Tested]

Looking for the working Vivo Y21 5G UFS ISP pinout without CPU drill? You have landed on the right page. The Vivo Y21 5G is built on the PD2542 PCB with a MediaTek Dimensity 6300 chipset and UFS storage. The ISP test points are easily accessible on the board surface—no need to drill through the CPU. Below is the tested pinout layout that works for FRP bypass, firmware flashing, and dead boot repair.

What Is ISP Pinout?

ISP (In-System Programming) is a technique that lets you access the UFS memory chip directly while it remains soldered on the motherboard. Instead of removing the chip, you solder fine wires to specific test points on the PCB and connect them to a supported box like UFI, Easy JTAG, or Medusa Pro. Once connected, you can read, write, or erase UFS memory — useful for FRP bypass, dead-boot recovery, and firmware flashing.

Why “Without CPU Drill”?

Many newer phones hide the UFS ISP points under the CPU or RAM chip, forcing technicians to drill through the IC to access them — a risky process that can permanently damage the board. The Vivo Y21 5G (PD2542) does not have this problem. The ISP pads are placed along the PCB edge under the metal shield, fully accessible with just a hot air station and a soldering iron.

Vivo Y21 5G Key Specifications

Model	Vivo Y21 5G
PCB Number	PD2542 (same as Y11 5G)
Chipset	MediaTek Dimensity 6300
Storage Type	UFS 2.2
RAM	4 / 6 / 8 GB
Display	6.74-inch HD+ 120Hz
Battery	6500 mAh
Android	16 (Funtouch OS)

Vivo Y21 5G UFS ISP Pinout Points

Once you remove the metal shield on the PD2542 PCB, look for the UFS ISP pads near the board edge. These are the five points you need to solder to:

💡 Tip: The Vivo Y21 5G shares the exact same PCB (PD2542) as the Vivo Y11 5G, so the ISP pinout is identical. If you already have the Y11 diagram, it will work for this model too.

Tools Required

• UFI Box / Easy JTAG Plus / Medusa Pro (with UFS support)
• 0.1 mm enameled copper wire or flexible jumper wires
• Fine tip soldering iron (350°C)
• Soldering flux and leaded solder
• Isopropyl alcohol (99%) + cleaning brush
• Multimeter for continuity testing
• Microscope or 10x magnifier
• Hot air station for shield removal

How to Connect – Step-by-Step Guide

1. Disconnect the battery—Always remove the battery connector first to avoid short circuits.
2. Remove the motherboard from the phone frame for easier access.
3. Remove the metal shield over the UFS area using hot air (280°C, low airflow).
4. Clean the PCB with IPA and a brush — dirt hides the tiny pads.
5. Identify the five ISP points — TX-OP, TX-ON, RX-ON, RX-OP, and GND near the board edge.
6. Tin the pads with a small amount of solder using flux.
7. Solder jumper wires to each pad. Keep wire length under 5 cm.
8. Secure the wires with Kapton tape so they don’t detach during handling.
9. Connect to your ISP box — Match the wire colors to your box pinout (TX → TX, RX → RX).
10. Verify continuity with a multimeter from box pin to each pad.
11. Run Identify UFS in UFI or Easy JTAG software.
12. Perform your operation—FRP reset, flash firmware, or dump UFS.

UFI Software Note: Use UFI v1.8.0.5 or later. Set I/O voltage to 1.8V and select UFS ISP protocol (not eMMC).

Common Issues & Fixes

• No UFS detection in software — Swap TX-OP with RX-OP and TX-ON with RX-ON. The TX and RX pairs are commonly reversed.
• Intermittent connection — Reflow the solder joints. A cold joint can cause dropouts.
• Tool shows “Unknown UFS” — Update to UFI v1.8.0.5+ and set voltage to 1.8V.
• Short circuit warning — Clean flux residue between pads. Check with multimeter.
• Can’t find the pads — Look under the shield near the PCB edge, not near the CPU. The points are not drilled under the chip.

Frequently Asked Questions