1. Sarrera
The GYSFLASH 12.12 is an advanced 12V 12A smart battery charger designed for optimal charging and maintenance of various 12V lead-acid batteries, including those found in cars, utility vehicles, motor homes, buses, commercial vehicles, and agricultural equipment. This manual provides essential information for safe and effective operation of your GYSFLASH 12.12 charger.
It features an 8-step intelligent charging curve to ensure maximum battery performance and longevity, along with specialized modes for different battery types and conditions.
2. Segurtasun-argibideak
Read all safety warnings and instructions carefully before using the charger. Failure to follow these instructions may result in electric shock, fire, or serious injury.
- Always ensure proper ventilation during charging to prevent gas accumulation.
- Do not charge frozen batteries. Allow them to warm up before charging.
- Avoid sparks or flames near the battery during charging, as batteries can emit explosive gases.
- Erabili begi-babesak eta arropa babesgarriak pilekin lan egiten duzunean.
- Disconnect the AC power supply before making or breaking connections to the battery.
- This charger is designed for 12V lead-acid batteries only (WET, MF, Ca/Ca, AGM, GEL, EFB). Do not use it for other battery types.
- The charger is protected against short circuits, polarity reversal, and overcharging. It also features anti-spark technology.
- The GYSFLASH 12.12 has an IP65 rating, indicating resistance to dust and water ingress. However, avoid submerging the unit.

3. Produktua amaitu daview
The GYSFLASH 12.12 is a compact and robust battery charger. Key components include:
- Unitate nagusia: Houses the charging electronics, control panel, and indicators.
- Kontrol-panela: Features LED indicators for charging status, selected mode, and potential errors.
- Modu hautatzeko botoia: Used to cycle through available charging modes.
- Bateria Clamps/Terminals: Gorria positiboa (+), beltza negatiboa (-).
- AC Power kablea: Connects the charger to a standard wall outlet.
- Kanpoko tenperatura sentsorea: Automatically adjusts the charging curve based on ambient temperature for optimal performance.

4. Konfigurazioa eta konexioa
Follow these steps to safely connect the GYSFLASH 12.12 charger to your battery:
- Bateria prestatu: Ensure the battery terminals are clean and free of corrosion. If charging an in-vehicle battery, ensure the vehicle's ignition is off and all accessories are disconnected.
- Bateriara konektatu:
- Konektatu gorria (+) charger clamp/terminal to the positiboa (+) bateriaren terminala.
- Konektatu beltza (-) charger clamp/terminal to the negatiboa (-) bateriaren terminala.
- For in-vehicle batteries, if the battery is not grounded to the chassis, connect the black (-) clamp to the negative (-) battery terminal. If the battery is grounded to the chassis, connect the black (-) clamp ibilgailuaren xasisera, bateriatik eta erregai-hoditik urrun.
- Konektatu energiara: Plug the charger's AC power cable into a standard electrical outlet. The charger will power on.
- Aukeratu modua: Press the mode selection button to choose the appropriate charging mode (see Section 5).
To disconnect, first unplug the charger from the AC outlet, then disconnect the black (-) clamp, eta ondoren gorria (+) clamp.

5. Funtzionamendu moduak
The GYSFLASH 12.12 offers several operating modes to optimize charging for different battery types and conditions. Use the mode selection button to cycle through these options.
- Normal Charge Mode: Standard charging for most 12V lead-acid batteries (WET, MF, Ca/Ca, GEL).
- AGM modua: Specifically designed for cold weather charging (below 5°C) and for Start & Stop batteries (EFB & AGM types). This mode adjusts charging parameters for these specific conditions.
- Freskatzeko modua: Used to recover deeply discharged batteries. This mode attempts to recondition batteries that have been left discharged for extended periods.
- Hornidura modua: Transforms the charger into a stabilized power supply. This mode is useful for:
- Maintaining battery health during vehicle demonstrations in showrooms.
- Preserving vehicle memory settings (e.g., radio codes, ECU data) during battery replacement.
The charger also features an Optimized Maintenance Charge, allowing it to remain plugged in indefinitely during winter months to maintain battery health without overcharging.

6. 8-Step Intelligent Charging Curve
The GYSFLASH 12.12 utilizes an advanced 8-step charging curve to ensure efficient, safe, and complete charging, maximizing battery lifespan and performance. The external temperature sensor automatically adjusts this curve based on ambient conditions.
- Analisia: Assesses battery condition and initial charge level.
- Berreskuratzea: Initiates a gentle charge for deeply discharged batteries (SOS Recovery for batteries >2V).
- Proba: Checks battery's ability to accept charge.
- Desulfation: Applies a pulsed charge to break down lead sulfate crystals, restoring battery capacity.
- Karga: Bulk charging phase, delivering maximum current until the battery reaches approximately 80% capacity.
- Xurgapena: Gradually reduces current while maintaining voltage to bring the battery to 100% charge.
- Freskatu: (If selected or needed) Further reconditions the battery.
- Karga flotagarria: Bateria karga osoan mantentzen du bolumen baxu eta konstante batekintage, preventing self-discharge.

7. Mantentzea
Proper maintenance ensures the longevity of your GYSFLASH 12.12 charger and the batteries it charges.
- Kargagailua zaintzea:
- Kargagailua garbi eta lehor mantendu. Garbitu zapi leun eta lehor batekin.amp oihal. Ez erabili disolbatzailerik.
- Gorde kargagailua leku fresko eta lehor batean erabiltzen ez duzunean.
- Kableak eta kloak ikuskatuamps regularly for damage. Replace if necessary.
- Bateria zaintzea:
- Ziurtatu bateriaren terminalak garbi eta korrosiorik gabe daudela.
- For conventional lead-acid batteries, check electrolyte levels periodically and top up with distilled water if needed (do not overfill).
- For optimal battery health, use the maintenance charge feature during long periods of inactivity.
8. Arazoak
If you encounter issues with your GYSFLASH 12.12, refer to the following common problems and solutions:
| Arazoa | Kausa posiblea | Irtenbidea |
|---|---|---|
| Kargagailua ez da pizten. | No AC power; faulty power cable. | Check AC outlet and power cable connection. Try a different outlet. |
| Charging indicator not active. | Bateriaren konexio okerra; bateriaren bolumenatage too low; incorrect mode selected. | Verify positive/negative connections. Ensure battery voltage is above 2V for recovery. Select appropriate mode. |
| Error LED illuminated. | Polarity reversal; short circuit; internal fault. | Disconnect charger, check connections for correct polarity. Inspect cables for damage. If error persists, contact support. |
| Bateria ez da guztiz kargatu denbora luzez igaro ondoren. | Battery deeply discharged or sulfated; battery capacity too large for charger; faulty battery. | Try "Refresh" mode for deeply discharged batteries. Ensure battery capacity is within charger's range (1.2-250 Ah). Test battery condition. |
| Charger automatically stops. | Battery disconnected; power cut; battery fully charged. | Check battery connections. The "Auto Restart" feature should resume charging after a power cut. If battery is full, this is normal operation. |
If the problem persists after attempting these solutions, please contact GYS customer support.
9. Zehaztapenak
| Ezaugarri | Xehetasuna |
|---|---|
| Marka | GYS |
| Eredua | GYSFLASH 12.12 (GYS - 029392) |
| Bolumen nominalatage | 12 V |
| Amparoa | 12 Amps |
| Bateriaren edukiera (kargatzen) | 1.2 Ah eta 250 Ah |
| Bateriaren edukiera (mantentze-lanak) | Gehienez 330 Ah |
| Bateria mota bateragarriak | Lead-acid (WET, MF, Ca/Ca, AGM, GEL, EFB, Start & Stop) |
| Karga Kurba | 8-step intelligent charging curve |
| Babes-balorazioa | IP65 (Dust and water ingress resistant) |
| Segurtasun Ezaugarriak | Short circuit, polarity reversal, overcharging protection, anti-spark, integrated temperature probe. |
| Neurriak (LxWxH) | 28 x 11 x 5.5 cm |
| Pisua | 950 g |
| Jatorrizko Herrialdea | Frantzia |

10. Bermea eta Laguntza
The GYSFLASH 12.12 charger comes with a 2 urteko bermea, erosketa-datatik aurrera fabrikazio-akatsak estaltzen ditu. Gorde erosketaren egiaztagiria berme-erreklamazioetarako.
For technical assistance, troubleshooting beyond this manual, or warranty service, please contact GYS customer support through their official website or your local distributor. Provide your product model number (GYSFLASH 12.12 or GYS - 029392) and a detailed description of the issue.
Official GYS Webgunea: www.gys.fr





