1. Introduction
The KOSO BA024B11 Super Slim Style Thermometer is a compact digital temperature gauge designed for monitoring engine or coolant temperatures. Its small size allows for versatile installation in various locations. The display features blue illuminated digits for enhanced visibility, particularly in low-light conditions. This device incorporates a warning function that activates a flashing display if the monitored temperature exceeds 120°C (248°F), providing a visual alert to the user.
2. Safety Information
- Ensure the power source is disconnected before installation to prevent electrical shock.
- Verify correct wiring polarity (positive and negative) to avoid damage to the unit.
- Avoid installing the thermometer in locations exposed to direct water spray or extreme moisture, as the unit is not fully waterproof.
- Handle wiring with care; the wires are fine gauge and can be damaged if stripped improperly.
- Consult a qualified technician if you are unsure about any installation steps.
3. Package Contents
Please check the package for the following items:
- KOSO BA024B11 Thermometer Unit
- Temperature Sensor
- Wiring Harness with Connectors
- Mounting Accessories (e.g., double-sided tape)
4. Setup and Installation
The KOSO BA024B11 thermometer is designed for straightforward installation, though some steps may require basic mechanical and electrical knowledge.
4.1. Sensor Installation
The temperature sensor features a 1/8" BSP (British Standard Pipe) parallel thread. Proper installation requires either an existing 1/8" BSP threaded port or drilling and tapping a new hole. An appropriate O-ring seal is necessary for a secure and leak-free connection. Ensure the sensor tip is immersed in the fluid to be measured for accurate readings.
4.2. Wiring Connection
The thermometer unit operates on a 12V DC power source. The wiring harness includes snap-together connectors for the sensor and display unit. Connect the bare wires (typically red for positive, black for ground) to a suitable 12V power source on your vehicle. Ensure all connections are secure and insulated. The wiring is fine gauge; exercise caution when stripping insulation to avoid damaging the copper strands.
4.3. Unit Mounting
The compact size of the thermometer unit (approximately 1 inch tall by 2 inches wide) allows for flexible mounting options. Use the provided double-sided tape or other suitable mounting hardware to secure the unit in a location that offers clear visibility and protection from direct elements. The wires exit from the right side of the unit, which should be considered for clean routing.

An image showing the compact KOSO BA024B11 digital thermometer unit, featuring a black casing with the KOSO logo and 'THERMOMETER' text. The display shows '°F'. Attached are the black wiring harness with a connector and two bare wires (red and black) for power connection.
5. Operating Instructions
Once properly installed and powered, the KOSO BA024B11 thermometer will automatically display the measured temperature on its blue LED screen. The display is designed for high readability.
5.1. Temperature Display
The thermometer displays temperature in Fahrenheit (°F). The large, blue LED digits ensure the reading is clear and easy to interpret at a glance, even in varying light conditions.
5.2. Warning Function
The unit is equipped with an alarm feature. If the monitored temperature reaches or exceeds 120°C (248°F), the digital display will begin to flash. This visual alert indicates a high-temperature condition, prompting the user to take appropriate action.
6. Maintenance
To ensure the longevity and accurate performance of your KOSO BA024B11 thermometer, follow these simple maintenance guidelines:
- Cleaning: Wipe the display and casing with a soft, damp cloth. Avoid using abrasive cleaners or solvents that could damage the plastic or display.
- Environmental Protection: While suitable for outdoor use, protect the unit from direct and prolonged exposure to heavy rain or extreme weather conditions to prevent potential damage.
- Connection Check: Periodically inspect all wiring connections to ensure they remain secure and free from corrosion.
7. Troubleshooting
If you encounter issues with your thermometer, consider the following:
- No Display: Check the 12V power connection. Ensure the positive and ground wires are correctly connected and receiving power. Verify that the wiring harness connectors are fully seated.
- Inaccurate Readings: Confirm the temperature sensor is properly installed and fully immersed in the fluid being measured. Ensure there are no air pockets around the sensor.
- Flashing Display (without high temperature): Recheck sensor connections. If the issue persists, the sensor or unit may require inspection.
- Intermittent Operation: Inspect all wiring for loose connections or damage. Ensure the unit is not exposed to excessive vibration or moisture.
8. Specifications
| Brand | Koso |
| Model Name | BA024B11 |
| Display Type | Digital LED |
| Display Color | Blue |
| Special Feature | Temperature Alarm (Flashing Display) |
| Upper Temperature Rating | 120°C (248°F) |
| Power Source | 12V DC (Vehicle Battery Powered) |
| Outer Material | Plastic |
| Response Time | Approximately 1 minute |
| Indoor/Outdoor Usage | Outdoor |
| Sensor Thread Type | 1/8" BSP Parallel Thread |
| Product Care | Wipe Clean |
9. Warranty and Support
For warranty information and technical support, please refer to the documentation provided with your purchase or visit the official Koso website. Keep your proof of purchase for any warranty claims.





