Samsung Galaxy S21 5G Repair

These are some common tools used to work on this device. You might not need every tool for every procedure.

Models

SM-G9910 (China), SM-G991B (International), SM-G991B/DS (Dual-SIM International), SM-G991N (South Korea), SM-G991U (USA AT&T), SM-G991U (USA), SM-G991U1 (USA Unlocked), SM-G991W (Canada)

The Samsung Galaxy S21 was announced in Samsung’s Galaxy Unpacked event on January 14th, 2021 and released on January 29th, alongside two other Galaxy Phones and a new pair of Galaxy Buds. The Galaxy S21 starts at $799 and comes in four colors: Phantom Violet, Phantom Grey, Phantom White, and Phantom Pink.

Compared to the Galaxy S20, the S21 has only a few minor changes–most of them downgrades to reduce the price (S20’s starting price of $999 to S21’s $799). Most notably, the rear cover is plastic instead of glass, which makes removing it easier. The screen is still 6.2 in with a 120 Hz refresh rate, but its pixel density dropped from 563 ppi to 421 ppi, the 1440x3200 resolution to 1080x2400, and the 89.5% screen-to-body ratio to 87.2%. The Galaxy S21 also weighs a little more than the S20: 5.96 oz and 5.75 oz respectively. To make up for this, the S21 boasts a Snapdragon 888 processor with integrated 5G modem and a 3D Sonic Sensor Gen 2 in-display fingerprint sensor with widened surface area, both from Qualcomm.

Internally, only three changes stand out as being important for repair: the vibration motor, the upper midframe, and the rear-facing camera adhesive. The Galaxy S20 has its vibration motor located near the bottom-left of the device brushing up against the USB-C port/daughterboard. Instead, the S21 has the vibration motor in the upper-left corner nestled between the motherboard and edge of the phone. To get to the vibration motor, you have to unfasten the upper midframe, which has almost double the amount of screws of the Galaxy S20; the upper midframe holds the motherboard, the camera assembly, and one 5G antenna in place. Finally, the rear-facing camera is protected by a risen-shell connected to the rear case and secured to the phone with strong adhesive.

Release date: January 2021

Body:

Dimensions and Weight: 151.7 x 71.2 x 7.9 mm (5.97 x 2.72 x 0.31 in), 169 g (5.96 oz)
Build: Glass front (Gorilla Glass Victus), plastic back, aluminum frame
SIM: Single SIM (Nano-SIM) or Dual SIM (2 Nano-SIMs + eSIM, dual stand-by
IP68 dust/water resistant (up to 1.5m for 30 mins)

Display:

Type: Dynamic AMOLED 2X, 120Hz, HDR10+, 1300 nits (peak)
Size: 6.2 inches, 94.1 cm² (~87.2% screen-to-body ratio)
Resolution: 1080 x 2400 pixels, 20:9 ratio (~421 ppi density)
Protection: Corning Gorilla Glass Victus
HDR10+
Always-on display
120Hz@FHD/60Hz@QHD refresh rate

Platform:

OS: Android 11, One UI 3.1
Chipset:
- Exynos 2100 (5 nm) - International
- Qualcomm SM8350 Snapdragon 888 5G (5 nm) - USA/China
CPU:
- Octa-core (1x2.9 GHz Cortex-X1 & 3x2.80 GHz Cortex-A78 & 4x2.2 GHz Cortex-A55) - International
- Octa-core (1x2.84 GHz Kryo 680 & 3x2.42 GHz Kryo 680 & 4x1.80 GHz Kryo 680) - USA/China
GPU:
- Mali-G78 MP14 - International
- Adreno 660 - USA/China

Memory:

Card slot: No
Internal: Qualcomm Snapdragon 888 with 8 GB of LPDDR5 memory (128 or 256 GB of storage)
UFS 3.1

Main Camera:

Triple:
- 12 MP, f/1.8, 26mm (wide), 1/1.76", 1.8µm, Dual Pixel PDAF, OIS
- 64 MP, f/2.0, 29mm (telephoto), 1/1.72", 0.8µm, PDAF, OIS, 1.1x optical zoom, 3x hybrid zoom
- 12 MP, f/2.2, 13mm (ultrawide), 1.4µm, Super Steady video
Features: LED flash, auto-HDR, panorama
Video: 8K@24fps, 4K@30/60fps, 1080p@30/60/240fps, 720p@960fps, HDR10+, stereo sound rec., gyro-EIS

Selfie Camera:

Dual: 10 MP, f/2.2, 26mm (wide), 1/3.2", 1.22µm, Dual Pixel PDAF
Features: Dual video call, Auto-HDR
Video: 4K@30/60fps, 1080p@30fps

Sound:

Loudspeaker: Yes, with stereo speakers
3.5 mm jack: No
32-bit/384kHz audio
Tuned by AKG

Communications:

WLAN: Wi-Fi 802.11 a/b/g/n/ac/6, dual-band, Wi-Fi Direct, hotspot
Bluetooth: 5.0, A2DP, LE
GPS: Yes, with A-GPS, GLONASS, BDS, GALILEO
NFC: Yes
Radio: FM radio (Snapdragon model only; market/operator dependent)
USB: USB Type-C 3.2, USB On-The-Go

Features:

Sensors: Fingerprint (under display, ultrasonic), accelerometer, gyro, proximity, compass, barometer
Bixby natural language commands and dictation
Samsung DeX, Samsung Wireless DeX (desktop experience support)
Samsung Pay (Visa, MasterCard certified)

Battery:

Li-Ion 4000 mAh, non-removable
Charging:
- Fast charging 25W
- USB Power Delivery 3.0
- Fast Qi/PMA wireless charging 15W
- Reverse wireless charging 4.5W

Miscellaneous: