Check the lock ring: This tool can be used to test the lock ring functionality. Antenna tester: Designed for car lock detection circuits and car key lock chip antenna testing. Small tip: If the light turns on but the car cannot be started, it may indicate a problem with the chip. Useful detection tool: A reliable and essential tool for automatic lock system diagnostics. How to use: Test the automatic lock system. If the light turns on, the lock ring is functioning properly. If the light does not turn on, there may be an issue with the lock ring. If the light turns on but the car still cannot be started, the issue may be with the chip. Inductive signal detection card: Capable of identifying lock ring issues. Durable in construction and easy to operate. Note: Installation guide is not included. Professional installation is strongly recommended. Please verify the product specifications to ensure compatibility and suitability for your needs. The image shown is a high-resolution rendering. Due to production variations across different batches, the actual product may have slight differences in appearance or color, which do not affect functionality. Color: Red Material: Plastic Package Contents: 5 x ECU Induction Signal Detection Card Package includes only the items listed above. Other accessories or products are not included. Note: Lighting conditions and monitor settings may cause slight variations in color between the product image and the actual item. Measurement tolerance is +/- 1-3 cm.