Does the GYSFLASH 121.12 CNT FV support ECU programming and diagnostics?

Yes. In Diagnostic mode it provides up to 120 A of stable support current. The output voltage can be set between 12.0–14.8 V in 0.1 V steps to meet OEM recommendations for ECU programming and advanced diagnostics.

Which battery types are supported?

12 V lead-acid (flooded, AGM, gel, calcium) and lithium iron phosphate (LFP / LiFePO4) batteries. Intelligent 8-step (lead-acid) and 9-step (LFP) charging curves optimize charge quality and battery life.

What battery capacities can it charge?

It handles batteries from approximately 5–1500 Ah, making it suitable for everything from small 12 V batteries to large, high-capacity units used in modern vehicles and fleets.

Can it act as a stabilized power supply?

Yes. Power Supply mode converts the unit into a continuous, stabilized DC source. Voltage is adjustable in 0.1 V increments and current in 1 A increments for precise support during testing and programming.

What is Flexible Voltage (FV) and why does it matter?

Flexible Voltage allows the charger to operate on a wide 85–265 V AC input (50/60 Hz). This ensures consistent, stable output in shops with 110 V or 230 V mains and improves portability across sites.

What can I do with the USB connectivity?

Add/modify charge profiles, import predefined configurations, update firmware, and export charge histories as CSV files. Via the SMC port you can add modules like a smart printer, barcode reader, or keypad for traceability.

What is Showroom mode used for?

Showroom mode compensates for accessory loads on display vehicles to keep the battery fully charged. It includes Auto-Restart after power loss and a Lock Showroom feature to prevent tampering.

Does it include safety protections?

Yes. Built-in protections include short-circuit, reverse polarity, over-voltage, overcharge, and thermal protection. Auto-Detect and Auto-Restart features enhance safety and uptime in workshop environments.

What are the dimensions, weight, and included cables?

The unit measures about 310 × 130 × 260 mm and weighs roughly 10.4 kg. It ships with 5 m / 25 mm² cables, and accessories like a trolley or wall bracket are available separately.

Is there a built-in tester?

Yes. Tester mode measures battery voltage, evaluates the starting system (starter + battery), and checks alternator status for quick diagnostics.

GysFlash 121.12 CNT Charger

Name: GYSFLASH 121.12 CNT FV – 120A Connected Battery Charger & Support Unit
Brand: GYS
SKU: DEFY-GYS-12112
Price: 1945 USD
Availability: InStock

Professional 120 A connected battery charger and support unit for 12 V lead-acid and lithium (LFP) batteries. The GYSFLASH 121.12 CNT FV delivers stabilized voltage for diagnostics, ECU programming, and showroom use. Features USB customization, intelligent 8/9-step charging, flexible voltage (85–265 V), and advanced safety protections. Perfect for workshops, dealerships, and industrial applications.

$1,945.00

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GYSFLASH 121.12 CNT FV – 120A Connected Battery Charger & Support Unit

Professional Power for Modern Vehicle Maintenance

The GYSFLASH 121.12 CNT FV is a high-power, fully connected 120 A battery charger and support unit built for automotive professionals. Featuring advanced inverter technology, it maintains a perfectly stabilized voltage for 12 V lead-acid or lithium (LFP) batteries during diagnostics, ECU programming, and servicing — ensuring manufacturer-approved performance.

With USB connectivity, the 121.12 CNT FV is 100% customizable, letting you add or edit charging profiles, import OEM-specific configurations, update firmware, and store detailed charge histories for full traceability.

Key Benefits at a Glance

High-Power Output: Up to 120 A continuous current for the most demanding diagnostic and programming tasks.
Flexible Voltage (FV): Operates on 85–265 V AC input — ready for global workshop environments.
Faster Charging: 8-step (lead) and 9-step (lithium) charging, up to 50% faster than traditional chargers.
Advanced Safety: Short-circuit, reverse-polarity, overcharge, over-voltage, and thermal protection.
Compact & Durable: Only 13 cm high — fits under vehicles; rugged carry case available.
Traceability Ready: Save, export, and print detailed charging records with optional modules.

Four Professional Operating Modes

1. Charging Mode

Smart, automatic charging for 12 V lead-acid (gel, AGM, liquid, calcium) or lithium (LFP) batteries from 5–1500 Ah.

2. Diagnostic Mode

Delivers up to 120 A continuous to support vehicle electronics during complex diagnostics and ECU programming — preventing voltage drop errors.

3. Showroom Mode

Keeps demonstration vehicles ready to start while powering accessories without draining the battery — includes Lock Showroom to prevent tampering.

4. Tester Mode

Checks battery voltage, starting system performance, and alternator condition — ideal for quick pre-service assessments.

Built-In USB Connectivity for Full Control

Add, delete, or modify charging profiles.
Import predefined configurations for specific applications.
Update onboard firmware for the latest features.
Retrieve charging history for reporting and compliance.
Integrate optional Smart Printer, barcode reader, or keypad via SMC port.

Why Choose the GYSFLASH 121.12 CNT FV?

Whether you’re running ECU reprogramming, ADAS calibration, chip-tuning, or simply maintaining showroom vehicles, this unit provides the stable, intelligent power supply modern vehicles demand. Built in Europe to the highest standards, the 121.12 CNT FV is trusted by OEMs and automotive professionals worldwide.

Technical Specifications

Max Current: 120 A
Battery Voltage: 12 V
Battery Capacity Range: 5–1500 Ah
Input Voltage Range: 85–265 V AC (50/60 Hz)
Charging Curve: 8-step (lead), 9-step (LFP)
Dimensions: 310 × 130 × 260 mm
Weight: 10.4 kg
Protection Class: IP20

Order your GYSFLASH 121.12 CNT FV today and equip your workshop with the power, precision, and reliability demanded by the most advanced vehicles.

Explore More Professional Starting & Power Support Solutions

Defy Diagnostics offers a complete range of GYS battery support units, supercapacitor jump starters, and Texa professional-grade diagnostic tools to keep your shop, fleet, or dealership running at full power.

GYSCAP 680E Supercapacitor Booster – Battery-free, 12V starting power with 1,600A cranking and 9,000A peak. Unlimited start cycles, instant recharge, and full safety protections — ideal for all weather conditions and site use.
STARTRONIC HYBRID 950 – Ultra-portable hybrid jump starter with supercapacitors and a lithium backup battery. Delivers 950A start power, multiple recharge options, and two “forcing” modes for stubborn starts.
TEXA Axone Voice Diagnostic Package – All-in-one diagnostic platform for cars, trucks, OHW, and powersports — OEM-level coverage with lifetime warranty (active subscription required).
Konfort Series A/C Service Machines – OEM-approved air conditioning service and recharge systems for professional workshops.
Fleet Tracker Pro App – Free for Defy Family members. Track vehicle service history, schedule maintenance, and reduce downtime across your fleet.

Whether you need stable battery support for ECU programming, high-amperage jump-starting in extreme conditions, or cutting-edge diagnostics, we have the tools to keep your operations powered and productive.