How to Fix Galaxy Note 5 Call Dropping, No 4G LTE, and Other Common Issues (2026 Guide)

The Samsung Galaxy Note 5 launched in 2015 and received its final software update (Android 7.0 Nougat) in 2018. Samsung no longer provides official support, but millions of these devices are still in use worldwide. If your Note 5 is dropping calls, can’t detect 4G LTE, or has other persistent issues, this guide covers the real fixes — not just “restart your phone.”

Important: Because the Note 5 no longer receives security patches or software updates, some issues (especially network-related ones) may be caused by carrier-side changes that can’t be fixed on the device. We’ll tell you when that’s the case so you don’t waste time troubleshooting a dead end.

Call Dropping Issues

Dropped calls on the Note 5 are usually caused by weak signal, a damaged SIM card, or a software glitch in the modem firmware. Here’s how to diagnose and fix it, starting with the most common cause.

Check Your Signal Strength

Before anything else, check your actual signal quality. Open your phone dialer and type *#0011# to enter Service Mode. This screen shows your real-time signal strength (RSSI), signal-to-noise ratio, and which band you’re connected to. If your RSSI is weaker than -100 dBm, your signal is marginal and drops are expected in that location.

Replace Your SIM Card

A worn or damaged SIM card is the #1 cause of random call drops that users overlook. SIM cards degrade over time, especially after years of use. Visit your carrier store and ask for a free SIM replacement — most carriers (AT&T, T-Mobile, Verizon) will swap it at no charge. After inserting the new SIM, test calls for 24 hours before trying other fixes.

Reset Network Settings

Go to Settings → Backup and reset → Reset network settings. This clears all saved Wi-Fi passwords, Bluetooth pairings, and mobile network configurations. Your phone will re-register with the carrier network from scratch, which often resolves persistent call-drop issues caused by stale network data.

Wipe the Cache Partition

This clears temporary system files without deleting your personal data:

Power off the phone completely.
Press and hold Volume Up + Home + Power simultaneously.
Release all buttons when the Android logo appears.
Use Volume Down to highlight Wipe cache partition and press Power to confirm.
Select Yes and wait for the process to finish.
Select Reboot system now.

Factory Reset (Last Resort for Software Issues)

If call drops persist after all the above steps, a factory reset eliminates any software-related cause. Back up your data first — this erases everything.

Go to Settings → Backup and reset → Factory data reset.
Tap Reset device, then Erase everything.
After the reset, test calls for a full day before reinstalling any apps. If drops continue on a clean device, the problem is hardware or carrier-related.

When It’s Not Your Phone

If calls still drop after a factory reset with a new SIM card and no apps installed, the issue is either hardware failure (damaged antenna or modem) or a carrier-side problem. Contact your carrier’s technical support:

AT&T: 1-800-331-0500
T-Mobile: 1-800-937-8997
Verizon: 1-800-922-0204

Ask specifically whether they’ve decommissioned any towers or bands in your area that the Note 5 relies on. As carriers roll out 5G infrastructure, older 3G/4G bands are being shut down, which directly affects legacy devices like the Note 5.

Galaxy Note 5 Won’t Detect 4G LTE

If your Note 5 suddenly lost 4G and is stuck on 3G or H+, the cause is almost always a SIM/carrier compatibility issue or incorrect network settings. Here’s how to fix it.

Verify Your SIM Card Supports 4G

Not all SIM cards are provisioned for LTE. If you recently swapped SIMs or are using a SIM from another carrier, confirm with your carrier that the SIM is LTE-enabled for your plan.

Check Network Mode Settings

Go to Settings → Mobile networks → Network mode and make sure it’s set to LTE/3G/2G (auto connect) — not 3G/2G only. If this option is missing, your carrier may have locked it on your device variant.

Use the Hidden Network Testing Menu

Dial *#*#4636#*#* to access the Testing menu. Tap Phone information and look for the Set preferred network type dropdown. Select LTE/GSM auto (PRL) or the closest LTE option available. This can override carrier restrictions on the network mode setting.

Verify APN Settings

Incorrect Access Point Name (APN) settings will prevent LTE connectivity. Go to Settings → Mobile networks → Access Point Names and verify your carrier’s APN is correctly configured. If you’re unsure, contact your carrier for the exact APN values or search “[your carrier] APN settings” online.

Band Compatibility Warning

The Note 5 comes in carrier-specific variants with different LTE band support:

Variant	Model	Key LTE Bands
AT&T	SM-N920A	2, 4, 5, 17 (700 MHz)
T-Mobile	SM-N920T	2, 4, 12
Verizon	SM-N920V	4, 13
Sprint	SM-N920P	25, 26, 41
Unlocked	SM-N920C	1, 3, 5, 7, 8, 20

If you’re using an unlocked or carrier-swapped Note 5, your device may not support the LTE bands your current carrier uses in your area. There is no software fix for this — the hardware radio simply can’t connect to those frequencies.

Screen Not Working After Water or Moisture Exposure

The Galaxy Note 5 has no official IP water resistance rating. If moisture got inside the device, here’s what actually works and what doesn’t.

What to Do Immediately

Power off the phone immediately. Do not attempt to charge it. Do not press buttons repeatedly.
Remove the SIM card tray (the Note 5’s back panel is not user-removable).
Pat the exterior dry with an absorbent cloth.
Place the phone near a fan blowing room-temperature air. Do not use a hair dryer — heat damages internal adhesives and can warp the display.
Wait at least 48 hours before attempting to power on.

What Doesn’t Work

Putting your phone in rice is largely a myth. Rice dust can clog ports, and rice absorbs moisture no faster than open air with a fan. Silica gel packets work marginally better but still won’t fix internal corrosion.

When to Seek Repair

If the screen shows discoloration, flickering, dead pixels, or doesn’t respond to touch after drying, the display assembly needs replacement. On the Note 5, this is typically a $80–$150 repair at a third-party shop. Samsung no longer services this device officially.

Screen Flashes a Different Color When Unlocking

If your Note 5 screen briefly flashes green, purple, or white before showing the lock screen, this is usually an early sign of display degradation (AMOLED burn-in or flex cable failure). Try these steps:

Disable Always On Display features if enabled — go to Settings → Display and turn off any ambient display or notification light features that keep the screen partially active.
Reduce screen brightness to 50% or lower to slow further OLED degradation.
If the flashing worsens or the screen develops persistent color tinting, the display panel is failing and will eventually need replacement.

A factory reset can rule out software causes, but display color flashing on AMOLED panels is almost always hardware.

No Signal at All — Phone Shows “No Service”

If your Note 5 shows “No Service” or “Emergency calls only” and none of the network fixes above help:

Check your IMEI: Dial *#06# — if the screen shows “null” or “unknown,” your IMEI has been corrupted. This is a serious issue that requires professional repair or firmware reflashing via Odin.
Try a different SIM card from the same carrier to rule out SIM failure.
Toggle Airplane Mode: Turn it on, wait 30 seconds, then turn it off. This forces a complete network re-registration.
Check for carrier account issues: Suspended accounts, unpaid balances, or IMEI blacklisting all show as “No Service” on the device.

Can’t Install Software Updates

The Galaxy Note 5’s final official firmware is Android 7.0 Nougat (released 2017, last security patch August 2018). If your phone says your software is up to date on Android 6.0 Marshmallow or 5.1.1 Lollipop, or if updates fail with the error “your operating system has been modified in an unauthorized way,” here’s what’s happening.

“Operating System Modified” Error

This message means Samsung’s KNOX security flag has been tripped — usually because the device was previously rooted, had a custom recovery installed, or had non-official firmware flashed. Samsung Smart Switch will also fail to update in this case.

The fix: Flash the official Nougat firmware manually using Odin:

Download Odin 3.13.1 (or newer) on a Windows PC and install Samsung USB drivers.
Download the correct firmware for your exact model variant (SM-N920A for AT&T, SM-N920T for T-Mobile, etc.) from SamMobile or a trusted firmware repository.
Boot your Note 5 into Download Mode: Power off → hold Volume Down + Home + Power → press Volume Up to confirm.
Connect via USB. Odin should show a blue/green box in the ID:COM section.
Load the firmware files into the AP, BL, CP, and CSC slots in Odin.
Click Start. Do not disconnect the phone until Odin shows “PASS.”

Warning: Flashing the wrong firmware variant (e.g., AT&T firmware on a T-Mobile device) can brick your phone. Always verify your exact model number in Settings → About device before downloading firmware.

Stuck on Android 5.1.1

Some carrier-locked Note 5 units never received the Nougat OTA push. The only way to get to Android 7.0 is to flash the firmware manually using the Odin method above. There will be no further Android updates beyond Nougat — this is the end of the road for this device.

Should You Still Use the Galaxy Note 5 in 2026?

The Note 5 is now over 10 years old. While it’s still a capable phone for basic tasks, there are real concerns:

No security updates since 2018 — the device is vulnerable to known exploits.
3G shutdown impact — AT&T and T-Mobile have shut down their 3G networks. If your Note 5 variant doesn’t support VoLTE (Voice over LTE) on your carrier, you may lose the ability to make calls entirely.
App compatibility — many apps now require Android 8.0 or higher and will no longer install on the Note 5.

If you’re experiencing persistent hardware issues, upgrading to a newer device is the most practical solution at this point.