2-in-1 LCD Water Temperature Gauge & Voltmeter – Digital 12 V/24 V with 10 mm Sensor

2-in-1 LCD Water Temperature Gauge & Voltmeter – Digital 12 V/24 V with 10 mm Sensor

The 2-in-1 LCD Water Temperature Gauge & Voltmeter is the smart choice for anyone wanting to monitor both coolant temperature and vehicle battery voltage in real-time. This compact gauge combines water temperature measurement and voltage measurement into a single clear digital instrument that works on both 12 V and 24 V electrical systems. Perfect for cars, vans, trucks, boats, or other vehicles where you need full control over the engine's cooling system and battery health.

Thanks to the improved sunshade design and optimized light intensity, you can easily read the screen even in strong sunlight. The imported key components provide higher precision, longer lifespan, and stable measurement results – whether you're driving in city traffic, on the highway, or off-road.

Specifications

• Model: 2-in-1 LCD Car Water Temp Gauge & Voltmeter
• Supply Voltage: 12 V and 24 V DC
• Water Temperature Measurement Range: –10 °C to 139 °C (–10 °F to 282 °F)
• Temperature Alarm: 95 °C –120 °C (adjustable via internal threshold)
• Accuracy: ±1%
• Operating Environment: 0 °C to 50 °C
• Sensor Size: 10 mm thread
• Cable Length: approx. 60 cm
• Connections: Red wire = +12/24 V, Red/black wire = Ground (–)
• Display: Digital LCD with sun protection and adjusted light intensity
• Consumption: Low power consumption for continuous operation
• Package includes: 1 × Water Temperature/Voltmeter 9–36 V, 1 × 10 mm sensor

Features & Benefits

• Two functions in one unit: Measure both water temperature and battery voltage on a single screen.
• High readability in sunlight: Built-in sun protection and optimized brightness ensure the display is clear even in bright daylight.
• Automatic temperature alarm: Visual flashing alarm at 95–120 °C warns directly of overheating.
• Accurate and stable: ±1% measurement precision with high-quality key components provides reliable results.
• Low power consumption: Suitable for both 12 V and 24 V systems without draining the vehicle's battery.
• Easy installation: Compact size, vibration-proof construction, and clear connecting cables.
• Long lifespan: Imported core components provide durable performance even in harsh environments.
• Wide range of applications: Suitable for cars, trucks, motorcycles, boats, RVs, and other vehicles where you want to monitor the cooling system and voltage.

With the 2-in-1 LCD Water Temperature Gauge & Voltmeter, you get both peace of mind and performance – you immediately see if the cooling system is approaching critical temperatures and simultaneously get a continuous view of the battery's status. This allows you to prevent expensive engine and electrical system damage before it occurs.

Compatibility

This 2-in-1 LCD water temperature gauge & voltmeter is designed for vehicles with both 12 V and 24 V electrical systems. It can be used on:

• Passenger cars, vans, and RVs
• Trucks and construction machinery
• Boats and marine applications
• Motorcycles, ATVs, and other recreational vehicles
• Stationary engines and generators that use 12 V/24 V battery systems

The product works equally well in petrol and diesel engines and can be mounted both in the dashboard and as an external gauge in the engine compartment or cabin, as long as it is protected from direct water ingress.

Step-by-step manual and installation guide

Follow the steps below to install and use the gauge safely. Read the entire guide before you begin.

Preparations

1. Check that you have the correct sensor (10 mm) and that both the gauge and sensor are undamaged.
2. Turn off the vehicle's ignition and disconnect the battery's negative terminal to avoid short circuits during installation.
3. Plan the placement of the gauge so that it is clearly visible but protected from direct moisture.

Mounting the water temperature sensor

1. Locate a suitable point in the cooling system where the sensor can measure the coolant temperature, e.g., on an existing sensor port or by mounting a T-adapter on a radiator hose.
2. Mount the sensor with a 10 mm thread and use thread sealant or a copper washer to prevent leakage.
3. Route the sensor cable (approx. 60 cm) to the location where the gauge will be installed and secure the cable so that it does not come into contact with moving or hot parts.

Electrical connection

• Red cable: +12 V or +24 V (connects to the vehicle's ignition-switched positive).
• Red/black cable: Ground (–) – connects to the vehicle's chassis or the battery's negative terminal.

4. Check that all connections are secure and that the cables are protected from chafing and heat.
5. Reconnect the battery's negative terminal and turn on the ignition to check that the gauge starts and displays both voltage and current water temperature.

Configuration and use

1. When the vehicle is running, the gauge automatically displays battery voltage (Volts) and water temperature (°C/°F).
2. If the coolant reaches the pre-set alarm temperature (95 – 120 °C), the display flashes to warn of overheating.
3. For best readability, the built-in light intensity automatically adjusts to avoid glare and protect the eyes.

Care and maintenance

• Clean the display and casing with a lightly dampened soft cloth – do not use solvents.
• Regularly check that the sensor is tightly fitted and that no coolant leaks have occurred.
• If the gauge is not used for extended periods, disconnect the power supply to avoid unnecessary battery drain.

Safety tips

• Always disconnect the battery's negative terminal before making electrical connections.
• Do not allow cables to rest against hot engine parts or moving components.
• Use only the included sensor – mixing with other brands can lead to inaccurate readings or damage the gauge.

Frequently Asked Questions (FAQ)

What does this 2-in-1 gauge measure?

It displays the coolant temperature via the included 10 mm sensor and the battery voltage (voltmeter) in real-time.

Does it fit both 12 V and 24 V?

Yes. The gauge supports 12–24 V (specified as 9–36 V in the package description). Connect the red wire to +12/24 V and the red/black wire to ground (–).

What temperature range can be displayed?

–10 °C to 139 °C (equivalent to –10 °F to 282 °F). Accuracy approximately ±1% within the specified operating environment of 0–50 °C.

Does it have an overheating alarm?

Yes. At 95–120 °C, a flashing alarm is activated on the display to warn of the risk of overheating.

Is the screen readable in strong sunlight?

Yes. The unit features a sunshade design and optimized light intensity for good readability in direct sunlight.

Must I use only the included sensor?

Yes. The instrument and sensor are matched. Mixing with other brands can lead to incorrect readings or damage to the equipment.

Where do I mount the 10 mm sensor?

In a suitable port in the cooling system (e.g., thermostat housing, radiator hose with a T-adapter, or an existing sensor port with a 10 mm thread) where the water flow is representative.

Can I switch between °C and °F?

The gauge supports both scales (–10 °C to 139 °C / –10 °F to 282 °F). Display mode may vary per version – please refer to the included instruction sheet.

How long is the sensor cable?

Approximately 60 cm. If necessary, you can extend it with high-quality shielded cable and carefully weather-seal the splices.

Is the gauge resistant to vibrations?

Yes. Production is adapted for anti-vibration/anti-bump in a vehicle environment, but always mount it stably and protected.

Does the display draw a lot of power?

No. It is designed for low power consumption and continuous operation in 12/24 V systems.

Can it be used in a boat/RV/motorcycle?

Yes, as long as the electrical system is 12/24 V and the sensor can be mounted in the cooling circuit with proper grounding and protection against water ingress.

The voltage shows incorrectly – what could be the cause?

Incorrect ground point, voltage drop in the power supply, or a bad connection. Use ignition-switched positive, a short and properly sized cable, and a clean ground point.

The temperature jumps – what do I do?

Check the grounding, wiring, that the sensor is tightly fitted in the water flow (not an air pocket), and that the cooling system is properly bled.

Tips & advice

• Choose measurement point carefully: A sensor port with good flow-through provides stable and representative temperature readings.
• Ignition-switched positive: Connect the red wire to a fused, ignition-switched +12/24 V to avoid battery drain during long-term parking.
• Protect wiring: Route cables away from hot and moving parts, use corrugated tubing and cable ties.
• Seal threads correctly: Use thread sealant/copper washer to prevent micro-leaks.
• Calibration check: If necessary, compare against OBD data or an external reference instrument within the same temperature range.
• Alarm level: Keep track of your engine's normal operating temperature – react immediately if the alarm is triggered.
• Service: Periodically check connections and ground points for optimal precision.

Troubleshooting

• Display dark: Check the fuse, that the red wire has +12/24 V, and the red/black wire has good ground. Measure with a multimeter.
• Voltage incorrect: Voltage drop in the power supply – try a shorter/thicker cable, move the power supply closer to the battery/fuse box.
• Temp shows 0 or —: Break in the sensor loop or poor connection. Check splices and sensor resistance.
• Unexpected alarm: Verify that the cooling system is bled and that the sensor is actually in the coolant, not in an air pocket.
• Flickering display in sunlight: Shade the front or angle the instrument. Check supply voltage and ground.

Package Contents

• 1 × 2-in-1 LCD Water Temperature Gauge & Voltmeter (9–36 V)
• 1 × Water Temperature Sensor 10 mm with cable (~60 cm)
• 1 × Quick guide/instruction sheet (version may vary)

Important Notes & Disclaimer

This product is intended for 12/24 V vehicle use. Always follow correct installation procedures. Use only the included matched 10 mm sensor; mixing with other brands can lead to inaccurate measurements and damage.

Mount the unit protected from direct water ingress and extreme temperatures (specified operating environment 0–50 °C). The manufacturer reserves the right to improve appearance and functions without prior notice.

Alarm/accuracy values apply under normal operating conditions. Installation and usage errors, incorrect cable dimensioning, or inadequate grounding can affect precision and function.

Use is at your own risk. Always check against vehicle manufacturer's specifications for safe temperature and voltage levels.