Ignition Sensors: Types and Technical Differences

Ignition detection is a fundamental aspect of vehicle telematics. In this article, we explore the different methods for detecting vehicle ignition and their technical characteristics.

Why Is Ignition Detection Important?

Ignition detection allows you to:

• Detect trips: Know when the vehicle is in use
• Calculate operating hours: Track engine running time
• Generate accurate reports: Differentiate between stops with engine on/off
• Optimize alerts: Trigger events based on ignition status

Detection Methods

1. ACC Wire (Direct Connection)

The most basic method connects to the vehicle's accessory wire.

Advantages:

• Simple installation
• Direct detection

Disadvantages:

• Requires physical wiring
• May not detect engine status (only ignition position)

2. Analog Voltage Detection

Uses voltage levels to determine ignition status.

How it works:

• Battery voltage typically drops when starting
• Running voltage stabilizes around 13.8-14.4V
• Off voltage remains at ~12.6V

Advantages:

• No additional wiring needed
• Works on any vehicle

Disadvantages:

• May give false readings with battery issues
• Requires proper threshold configuration

3. Digital Input

Uses a digital input connected to ignition signal.

Advantages:

• Clean on/off signal
• Reliable detection

Disadvantages:

• Requires proper installation point
• Need to identify correct wire

4. CAN Bus Detection

Reads ignition status directly from vehicle ECU via CAN Bus.

Advantages:

• Most accurate method
• No additional wiring
• Additional data available (RPM, etc.)
• Detects actual engine running status

Disadvantages:

• Requires CAN Bus compatible vehicle
• May need vehicle-specific configuration

Comparison Table

Method	Accuracy	Installation	Compatibility
ACC Wire	Medium	Complex	Universal
Analog	Medium	Simple	Universal
Digital	High	Medium	Universal
CAN Bus	Highest	Simple	Modern vehicles

Rinho Implementation

All Rinho devices support multiple ignition detection methods:

Spider IoT

• Analog voltage detection (built-in)
• CAN Bus ignition status
• 1 configurable digital input

Smart IoT

• Analog voltage detection (built-in)
• CAN Bus ignition status
• Multiple digital inputs
• Configurable thresholds

Recommended Configuration

For best results, we recommend:

1. Modern vehicles (2010+): Use CAN Bus detection
2. Older vehicles: Use analog voltage with proper thresholds
3. Critical applications: Combine methods for redundancy

Practical Tips

• Voltage thresholds: Set ignition ON above 13.2V for analog detection
• Debounce time: Use 3-5 second delay to avoid false triggers
• Testing: Verify detection works in all scenarios (start, idle, off)

Conclusion

Choosing the right ignition detection method depends on your specific requirements and vehicle type. Rinho devices provide flexibility to use the best method for each application.

For installation assistance, contact us.