1. Introducere
This manual provides detailed instructions for the safe and effective operation of your Mastfuyi FY8912B 12V/24V Car Battery Tester. This device is designed to analyze the health of 12V and 24V lead-acid batteries, including regular flooded, AGM flat plate, AGM spiral, GEL, and EFB types. It also performs cranking and charging system tests for various vehicles such as cars, trucks, vans, boats, motorcycles, ATVs, and SUVs.
2. Informații de siguranță
Always observe the following safety precautions when using the battery tester to prevent injury or damage to the device or vehicle.
- Protecția ochilor: Always wear appropriate eye protection when working near batteries.
- Ventilare: Ensure adequate ventilation when testing batteries, as they can emit explosive gases.
- Avoid Sparks: Do not smoke or allow sparks or flames near the battery or engine during testing.
- Acid bateriei: Battery acid is corrosive. Avoid contact with skin, eyes, or clothing. In case of contact, flush immediately with water and seek medical attention.
- Polaritate: Conectați cl. roșuamp la terminalul pozitiv (+) și cl negruamp to the negative (-) terminal. Incorrect connection can damage the tester or battery. The device includes reverse polarity protection.
- Conexiuni sigure: Asigurați clamps are securely attached to battery terminals to avoid poor contact and inaccurate readings.
- Putere dispozitiv: The tester is powered directly by the 12V/24V battery being tested. No internal batteries are required.
3. Produs terminatview
3.1 Caracteristici cheie
- Compatibilitate largă: Supports 12V and 24V lead-acid batteries (Flooded, AGM Flat Plate, AGM Spiral, GEL, EFB).
- Broad Test Range: 100-2000 CCA.
- Precizie ridicată: Provides 99.5% accuracy for reliable results.
- Multiple Standards: Adheres to CCA, DIN, EN, SAE, IEC, AH standards.
- Comprehensive Tests: Performs Battery Health Check, Cranking System Test, Charging System Test, and Maximum Load Test.
- Interfață ușor de utilizat: Features a large LCD display and intuitive button controls.
- Protecții de siguranță: Includes anti-reverse wiring, anti-over-voltage, și protecție la scurtcircuit.
3.2 Conținutul pachetului
- Mastfuyi FY8912B Car Battery Tester
- Copper Terminal Bolts (for improved contact)
- Geanta de depozitare
3.3 Aspectul dispozitivului
The image below illustrates the main components of the Mastfuyi FY8912B battery tester, including the display, control buttons, and connection clamps.

Image 1: Mastfuyi FY8912B Car Battery Tester, showing the main unit, red and black alligator clamps, a storage bag, and two copper terminal bolts.
The device features a clear LCD screen and ergonomic design for ease of use. Its compact dimensions are suitable for various applications.

Image 2: Mastfuyi FY8912B Car Battery Tester displaying its dimensions (163mm/6.42in height, 88mm/3.46in width) and icons representing various test capabilities like State of Charge, State of Health, Reverse Polarity Protection, Voltage Test, Discharging Test, Resistance Test, Cranking Test, Load Test, and Charging Test.
4. Configurare
4.1 Conectarea testerului
To ensure accurate readings and proper operation, follow these steps to connect the battery tester:
- Asigurați-vă că contactul vehiculului este oprit și toate accesoriile sunt oprite.
- Conectați roşu pozitiv (+) clamp la borna pozitivă (+) a bateriei.
- Conectați negru cl negativ (-)amp la borna negativă (-) a bateriei.
- Testerul se va porni automat odată ce este conectat corect.
- If battery terminals are corroded or too short for a secure connection, use the included copper terminal bolts. Attach them to the battery terminals first, then connect the tester clamps to the bolts for optimal contact.

Image 3: Illustration demonstrating the use of pure copper terminal bolts to extend battery terminals for a better connection, preventing issues caused by loose contact.
5. Instrucțiuni de utilizare
5.1 Navigarea în meniu
Once powered on, the main menu will appear on the LCD screen. Use the following buttons to navigate:
- Săgeți sus/jos: Derulați prin opțiunile din meniu.
- Buton OK: Select a highlighted option or confirm an action.
- Butonul ESC: Go back to the previous screen or cancel an operation.
- Buton RST: Reset the device or restart a test.
5.2 Selecting a Test Mode
From the main menu, you can select different test modes. The device offers both quick and precise testing options.

Image 4: The tester's screen displaying the 'Mode' selection, offering '1. Quick Test' and '2. Precise Test' options.
For a quick test, you may only need to input the battery capacity. For a precise test, you will input specific battery standards like CCA, IEC, EN, DIN, SAE, or JIS.
6. Testing Modes
The Mastfuyi FY8912B offers several testing functions to comprehensively assess your vehicle's battery and electrical system.
6.1 Testul bateriei
This test evaluates the overall health of the battery, providing information on its State of Health (SOH), State of Charge (SOC), Internal Resistance (IR), and a general testing conclusion. It supports various 12V/24V lead-acid battery types.

Image 5: The tester displaying battery test results, including Voltage (12.54V), SOC (75%), CCA (462), SOH (100%), and Internal Resistance (6.03mΩ), with a conclusion of 'talented'. The image also highlights compatibility with Regular-Flooded, AGM Flat Plate, AGM Spiral, GEL, and EFB battery types.
6.2 Cranking System Test (Starter Test)
Acest test analizează volumul real de demarajtage of the engine to determine if the starter motor is functioning weakly or normally. It helps diagnose issues with the starting system.
- Select 'Starter Test' from the main menu.
- Urmați instrucțiunile de pe ecran pentru a porni motorul.
- Testerul va afișa volumul de porniretage and a conclusion.

Image 6: The tester's screen during a 'Cranking/Starter Test', prompting the user to 'Please start the engine!' and showing a static voltage de 12.54V.
6.3 Testarea sistemului de încărcare
This test checks the alternator's continuous output while the engine is running to ensure it provides proper power to the battery and the vehicle's electrical system. It assesses different parts of the charging system, including the alternator, starter, generator, and rectifier diode.
- Select 'Charging SYS' from the main menu.
- Follow the on-screen instructions, which typically involve starting the engine and possibly revving it to a certain RPM.
- The tester will display the maximum and minimum voltages, indicating the charging system's performance.

Image 7: The tester's screen displaying results from a 'Charging Test', showing Max Voltage (12.51V < 30.0V), Current Volt (12.51V), and Min Voltage (12.6V < 26.6V), indicating the health of the charging system.
6.4 Test de sarcină maximă
This test detects the output voltage under maximum load conditions, including the battery, alternator, and power station, providing accurate data in seconds.
- Select 'Maximum load' from the main menu.
- Follow any specific prompts on the screen.
- The tester will display the current and minimum voltages under load, along with a conclusion.

Image 8: The tester's screen displaying results from a 'Maximum Load' test, showing Current Volt (12.53V) and Min Voltage (12.62V < 25.6V), with a conclusion of 'Too low'.
7. Protecții multiple
The Mastfuyi FY8912B is designed with multiple safety features to ensure reliable and secure operation during testing.
- Protecție polaritate inversă: Prevents damage if the clamps are connected incorrectly (positive to negative, or vice versa).
- Overvoltage Protecție: Safeguards the device from excessively high input voltages.
- Protecție la scurtcircuit: Protects against damage in case of a short circuit during testing.
- Poor Contact Protection: Enhanced internal input protection measures address issues like poor contact of the test chuck.

Image 9: The tester's screen showing the main menu, alongside icons representing 'Reverse Polarity Protection', 'Overvoltage Protection', and 'Short Circuit Protection', emphasizing the device's safety features.
8. Depanare
If you encounter issues while using the Mastfuyi FY8912B, refer to the following common problems and solutions:
- Dispozitivul nu pornește:
- Asigurați clamps are securely connected to the battery terminals. The device draws power directly from the battery.
- Check if the battery has sufficient charge (above 8V for 12V systems) for the tester to power on. If the battery is completely dead, the tester may not activate.
- Verify correct polarity: Red to positive (+), Black to negative (-).
- Inaccurate Readings or "Poor Connection" Message:
- Clean battery terminals to remove dirt, corrosion, or oxidation.
- Asigurați clamps are firmly attached to the battery terminals. Wiggle them slightly to establish better contact.
- Use the provided copper terminal bolts if the battery terminals are difficult to connect to directly.
- Buttons Seem Unresponsive or Stuck:
- Press buttons firmly and ensure they return to their original position.
- If a button remains physically stuck, gently try to free it. Avoid excessive force.
- Disconnect and reconnect the tester to reset the device.
- Test Results Seem Incorrect:
- Verify that the correct battery type (Flooded, AGM, GEL, EFB) and CCA rating (if applicable) have been entered into the tester.
- Ensure all vehicle accessories are off during testing to avoid parasitic draws affecting results.
- Repeat the test to confirm consistency of results.
9. Specificații
Below are the technical specifications for the Mastfuyi FY8912B Car Battery Tester:
| Caracteristică | Caietul de sarcini |
|---|---|
| Marca | Mastfuyi |
| Numărul de model | Anul fiscal 8912B |
| Sursa de alimentare | Alimentat cu baterie (de la o baterie testată) |
| Tip de măsurare | Voltmetru |
| Interval de testare | 100-2000 CCA |
| Tipuri de baterii acceptate | Baterie obișnuită inundată, placă plată AGM, spirală AGM, GEL, EFB |
| Standarde de baterii acceptate | CCA, BCI, CA, MCA, JIS, DIN, SAE, EN, IEC, AH |
| Greutatea articolului | 431 g |
| Dimensiuni pachet | 23.39 x 15.8 x 5.41 cm |
| Baterii incluse | Nu |
10. Întreținere
To ensure the longevity and optimal performance of your Mastfuyi FY8912B battery tester, follow these maintenance guidelines:
- curatenie: Ștergeți dispozitivul cu o lavetă moale și uscată după fiecare utilizare. Nu utilizați produse de curățare abrazive sau solvenți.
- Depozitare: Store the tester in its provided storage bag in a cool, dry place, away from direct sunlight and extreme temperatures.
- Îngrijirea cablului: Inspectați cablurile și cl-ulampVerificați periodic pentru a depista orice semne de deteriorare, uzură sau coroziune. Înlocuiți dacă este necesar.
- Șuruburi terminale: Keep the copper terminal bolts clean and free of corrosion for consistent good contact.
11. Garanție și asistență
Mastfuyi oferă o Garanție necondiționată de 48 de luni for this product. This warranty covers manufacturing defects and ensures lifetime after-sales service. For any support inquiries, technical assistance, or warranty claims, please contact Mastfuyi customer service through your purchase platform or the official Mastfuyi support channels.





