1. Introduction
The Code Alarm MV3 Dual Zone Microwave Sensor is designed to detect movement within a vehicle's interior, providing an advanced layer of security. Utilizing unique RF technology, this sensor identifies moving objects, making it an effective solution for vehicle intrusion detection, particularly suitable for convertibles or vehicles where traditional sensors may be less effective.
This manual provides essential information for the proper installation, operation, and maintenance of your MV3 sensor.

Image 1.1: The Code Alarm MV3 Dual Zone Microwave Sensor, including the sensor unit, wiring, and introductory documentation, as packaged for retail.
2. Product Overview
The MV3 sensor is a highly reliable vehicle intrusion detection device. It operates by emitting microwave signals and detecting disturbances caused by movement within its detection zones. The dual-zone capability allows for distinct detection areas, typically an outer warning zone and an inner full-alarm zone.
- Reliable Detection: Utilizes RF technology for consistent and accurate movement detection.
- Dual Zone Capability: Provides both a pre-warning and a full-alarm trigger based on proximity of movement.
- Wide Range: Capable of detecting movement up to 12 meters.
3. Setup and Installation
Proper installation is crucial for the optimal performance of the MV3 sensor. It is strongly recommended that installation be performed by a qualified professional to ensure correct wiring and calibration, especially as additional parts or labor may be required depending on the vehicle's existing security system.
3.1 Mounting
The sensor should be securely mounted within the vehicle's interior, typically in a central location that allows for unobstructed microwave signal propagation throughout the cabin. Common mounting locations include under the dashboard, center console, or rear deck. Ensure the mounting surface is stable and free from vibrations.
3.2 Wiring
The MV3 sensor requires a corded electric connection to the vehicle's power system and integration with a compatible alarm or security module. Refer to the wiring diagram provided with your specific Code Alarm CA Series System for detailed connection instructions. Incorrect wiring can damage the sensor or the vehicle's electrical system.
3.3 Calibration
After physical installation and wiring, the sensor's sensitivity and detection zones must be calibrated. This typically involves adjusting potentiometers on the sensor unit to define the outer (warning) and inner (full alarm) detection boundaries. Test the sensor's response with the vehicle's windows up and down, and with any convertible tops in their normal positions, to ensure accurate detection without false alarms.
4. Operating Instructions
Once installed and calibrated, the MV3 sensor operates automatically in conjunction with your vehicle's security system. When the security system is armed, the microwave sensor becomes active.
- Warning Zone: If movement is detected in the outer zone (e.g., someone leaning into an open window), the sensor will trigger a pre-warning signal, typically a series of chirps from the alarm system.
- Full Alarm Zone: If movement is detected in the inner zone (e.g., someone entering the vehicle), the sensor will trigger the full alarm, activating the siren and other alarm features.
The sensor's maximum detection range is 12 meters, but effective range within a vehicle will vary based on interior layout and calibration settings.
5. Maintenance
The Code Alarm MV3 sensor is designed for minimal maintenance. To ensure continued optimal performance:
- Keep Clean: Periodically wipe the sensor unit with a soft, dry cloth to remove dust or debris that could obstruct its operation.
- Avoid Obstructions: Ensure no new objects (e.g., large bags, clothing) are placed directly in front of or covering the sensor, as this can interfere with its detection capabilities.
- Regular Testing: Occasionally test the sensor's functionality by simulating intrusion to confirm it triggers the warning and full alarm as expected.
6. Troubleshooting
If you experience issues with your MV3 sensor, consider the following troubleshooting steps:
- False Alarms: If the sensor triggers false alarms, the sensitivity may be set too high. Re-calibrate the sensor, reducing the range of the detection zones. Ensure no external factors (e.g., strong vibrations, large passing vehicles if parked very close) are causing interference.
- No Detection: If the sensor fails to detect movement, check the wiring connections to ensure they are secure and correctly installed. Verify the sensor is receiving power. The sensitivity may be set too low, requiring re-calibration to increase the detection range.
- Intermittent Operation: Check for loose connections or potential interference from other electronic devices in the vehicle.
For persistent issues, it is recommended to consult a professional installer or contact Code Alarm customer support.
7. Specifications
| Brand | Code Alarm |
| Model | MV3 |
| Color | Black |
| Power Source | Corded Electric |
| Item Weight | 16 ounces (1 pound) |
| Maximum Range | 12 Meters |
| Mounting Type | Vehicle Interior Mount (Wall Mount listed in generic specs) |
| Compatible Devices | MV3 (Code Alarm CA Series Systems) |
| UPC | 044476065736, 096204007136 |
| Package Dimensions | 6.2 x 5.7 x 1 inches |
8. Warranty Information
The Code Alarm MV3 Dual Zone Microwave Sensor is covered by a manufacturer's warranty. Please retain your proof of purchase. It is important to note that the WARRANTY IS VOID IF THE LABEL IS REMOVED from the product. For specific warranty terms and conditions, please refer to the documentation included with your purchase or contact Code Alarm customer support.
9. Support and Contact Information
For technical assistance, installation inquiries, or warranty claims, please contact Code Systems, Inc.:
- Address: 525 Minnesota Drive, Troy, Michigan 48083, USA
- Phone: 1-800-421-3209
- Website: www.code-alarm.com
Product features and specifications are subject to change without notice. Not all vehicles can support all features and functions of the CA Series Systems. In addition, the CA series includes features and functions that may require additional parts/labor for proper installation and operation. See your sales associate for details.





