Simrad NSS touchscreen only works in some areas — dead in others. Hardware?

Dead zones that are consistent and in the same location suggest digitizer damage or the evo2 flex cable issue. Dead zones that move or change suggest software/calibration. Persistent physical dead zones generally require service.

How old is my NSS evo2? Where is the serial number?

Serial number is on a label on the rear of the unit. Simrad's website supports serial number lookup for warranty status and production date. Units produced before mid-2015 are more likely to have the flex cable issue.

Simrad NSS touchscreen works fine but the rotary knob doesn't — related?

No — the rotary encoder and touchscreen are separate input paths. Knob failure is usually a dirty or worn encoder; clean with contact cleaner or replace the encoder component (accessible with the unit removed from the mount).

FixForge › Marine › Marine Electronics › Simrad NSS Touchscreen Frozen

Simrad NSS Touchscreen Frozen: Step-by-Step Diagnostic

A frozen Simrad NSS or NSS evo2 touchscreen almost always responds to a hard reset or firmware update. Early NSS evo2 units (2013–2015) have a known flex cable weakness that causes intermittent touchscreen failure — if you have an evo2 and the touchscreen fails progressively over months, this is the likely cause and requires service.

Last Updated: June 2026

Fast Answer

Hold the power button 5–8 seconds to force a hard reset — if the unit is frozen on a screen or completely unresponsive, this clears most firmware hangs. If that doesn't work: remove all chart cards from the card slots and power cycle. A corrupted chart card can cause the OS to hang during card enumeration at startup, preventing touchscreen initialization.

Hard reset — hold power 5–8 sec

Forces a hardware-level power cutoff. Works for most firmware hangs regardless of what's on screen.

Remove chart cards

Corrupted chart cards cause OS hang during startup. Remove all, power cycle, test touchscreen.

Check NSS evo2 flex cable

Early evo2 units (2013–2015) have known flex cable failures causing progressive touchscreen degradation.

Update firmware via SD card

Older NSS firmware has touchscreen responsiveness bugs. Update to current firmware.

Hard Reset Procedure

The Simrad NSS hard reset cuts power to the processor regardless of software state. It resolves firmware hangs, infinite loading screens, and unresponsive OS states.

Press and hold the power button (physical button on the front of the unit) for 5–8 seconds.
The unit will power off. Wait 15 seconds.
Power on normally.
Test touchscreen before doing anything else — if the OS is clean, touchscreen should respond within 30 seconds of boot completion.

Chart Card Removal

The NSS OS enumerates SD cards during startup. A corrupted card can cause the OS to hang partway through initialization, which presents as a unit that appears to be on (backlight is on, maybe showing a logo or partial screen) but with an unresponsive touchscreen — because the OS hasn't finished loading.

Power off the unit.
Remove all chart cards from the SD slots (NSS typically has two slots on the front panel).
Power on. Wait for the full boot sequence to complete (30–60 seconds) before testing touchscreen.
If touchscreen works without cards: reinsert one card at a time to identify the corrupted one.

NSS evo2 Flex Cable Issue

Early Simrad NSS evo2 units built between 2013 and 2015 have a documented internal flex cable connecting the touchscreen digitizer to the main board. The cable routes through an area subject to heat cycling and vibration, and it can develop micro-fractures that cause intermittent then permanent touchscreen failure. Symptoms:

Touchscreen works when cold, fails after the unit warms up
Intermittent dead zones that grow over months
Screen works after the unit sits overnight but fails an hour into use

This is not software-fixable. The flex cable repair requires disassembly and is best done by Simrad's service network or a qualified marine electronics technician. Simrad has acknowledged this issue and has offered repair assistance — contact Simrad support with your unit serial number to check if your unit is eligible for repair assistance.

Firmware Update

Simrad released multiple NSS firmware updates that addressed touchscreen sensitivity and responsiveness issues. Check your current firmware version: Settings > System > About. Compare to the latest on Simrad's website. Updates are applied via SD card:

Download the firmware package from simrad-yachting.com (support section).
Extract the downloaded file — copy the firmware file to the root of a FAT32-formatted SD card.
Insert the card and navigate to Settings > System > Software Update.
Follow the on-screen prompts. Keep the unit powered via stable power during the update.

Class 10 SD Card for Simrad NSS Firmware Update

FAT32 compatible. Required for reliable NSS firmware updates and chart card replacement.

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