Preparing a König race car for a test day involves several crucial steps to ensure peak performance and safety.

1. **Inspection**: Begin with a thorough inspection of the car. Check for any visible damage, leaks, or loose components.

2. **Race Harness**: Install the race harness securely. Ensure all belts are correctly threaded and tightened. The harness should be snug but comfortable, allowing the driver minimal movement.

3. **Wheel Alignment**: Adjust the wheel alignment according to the track specifications. This includes setting the camber, caster, and toe angles to optimize handling and tire wear.

4. **Tire Pressure**: Check and adjust the tire pressure. Refer to the manufacturer’s recommendations and consider the track conditions.

5. **Fluid Levels**: Check all fluid levels including oil, coolant, brake fluid, and power steering fluid. Top up as necessary.

6. **Brakes**: Inspect the brake pads, rotors, and lines. Ensure there is no excessive wear and that the brakes are functioning correctly.

7. **Suspension Setup**: Adjust the suspension settings for the track. This might include tuning the dampers, springs, and anti-roll bars.

8. **Safety Equipment**: Verify that all safety equipment is in place and in good condition. This includes the fire extinguisher, roll cage, and any required driver safety gear.

9. **Fuel**: Fill the fuel tank and check for any leaks in the fuel system.

10. **Electronics**: Ensure all electronic systems, including telemetry, data logging, and communication devices, are working properly.

11. **Engine Warm-Up**: Start the engine and allow it to warm up gradually. Listen for any unusual noises and check for leaks.

12. **Final Checks**: Conduct a final walk-around, checking for anything that might have been missed. Ensure all fasteners are tight and nothing is out of place.

By meticulously preparing the König race car, you can ensure a successful and safe test day, allowing you to focus on performance and data collection.