Telematics
The integrated use of telecommunications and informatics to transmit vehicle location, engine data, driver behavior, and operational metrics over cellular networks to a central platform, forming the data foundation of modern fleet management.
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Compare Telematics software →What Telematics Actually Measures
A telematics device is a hardware unit installed in or integrated into a vehicle that collects data from multiple vehicle systems, packages that data, and transmits it over a cellular network to a cloud platform. The data collected spans four domains: location (GPS coordinates, heading, altitude, speed), vehicle systems (engine RPM, coolant temperature, oil pressure, fuel level, odometer, fault codes via OBD-II or J1939/J1708 for heavy vehicles), driver behavior (hard braking, harsh cornering, rapid acceleration, seat belt status, idle time), and operational context (trip start/end times, geofence events, job assignments).
Telematics Data Types by Vehicle Interface
| Interface | Vehicle Type | Data Available | Installation |
|---|---|---|---|
| OBD-II port | Light vehicles (cars, vans, pickup trucks) | Location, basic fault codes, fuel level, odometer | Plug-and-play, no wiring |
| J1939 CAN bus | Class 4–8 trucks, buses, construction equipment | Full engine data, transmission, axle load, fuel consumption | Hardwired — professional install |
| J1708 / J1587 | Older heavy vehicles (pre-2000) | Limited engine data, basic fault codes | Hardwired — professional install |
| OEM embedded | New vehicles with factory telematics (Ford Pro, GM Fleet) | Full OEM data, no aftermarket device needed | Factory-installed |
| Asset tracker (GPS-only) | Trailers, equipment, non-powered assets | Location and motion only — no engine data | Battery-powered, magnetic mount |
How Telematics Data Reaches the Platform
Most modern telematics devices use 4G LTE cellular networks (with 5G emerging for high-data applications). The device buffers data locally when cellular coverage is unavailable and transmits the backlog when coverage returns. Data is encrypted in transit using TLS. Update frequency varies by event type: GPS position typically every 5–60 seconds while moving, engine data every 1–60 seconds depending on configuration, and event-triggered data (hard brake, fault code) sent immediately regardless of update interval. High-frequency 1Hz GPS (one update per second) is available on premium plans but significantly increases data costs and storage requirements.
Real-World Example: Telematics ROI in a 120-Vehicle Service Fleet
A facilities management company operating 120 service vans across three cities implemented Samsara telematics after annual fuel costs exceeded $1.2 million. In the first 12 months: idle time monitoring revealed average idle time of 47 minutes per vehicle per day across the fleet — after implementing an idle alert policy and automatic engine-off reminders, idle time fell to 18 minutes, saving approximately $86,000 in fuel. Speeding alerts and monthly driver coaching reduced hard-braking events by 41%, cutting rear-end incidents from 9 to 2 that year, saving an estimated $140,000 in insurance claims and deductibles. GPS utilization reporting showed 12 vehicles running at less than 40% utilization — three were reassigned, avoiding three planned new-vehicle purchases at $38,000 each. Total first-year documented savings: $448,000 against a $96,000 annual platform cost.
- Match the device interface to your vehicle types — OBD-II for light vehicles, J1939 for heavy trucks
- Confirm cellular network coverage in your operating region — some rural operators need satellite-capable devices
- Verify the telematics vendor supports your specific vehicle makes and models for engine data (coverage varies significantly)
- Check data update frequency and whether higher-frequency options are available at additional cost
- Confirm historical data retention period — some vendors purge data after 12 months, limiting long-term trend analysis
- Ask whether the platform supports mixed-fleet configurations (telematics devices + OEM embedded data sources)
- Evaluate driver privacy features — can location tracking be suspended during off-duty personal use?
- Verify API access is included in your contract, not sold as a separate add-on
Heavy Vehicle Telematics: J1939 vs. OBD-II
J1939 is the CAN bus standard used in Class 4–8 commercial trucks (Peterbilt, Kenworth, Freightliner, Volvo, Mack). It provides dramatically richer data than OBD-II: real fuel consumption in gallons per hour (not estimated), turbocharger boost pressure, transmission gear position, axle weight (on equipped vehicles), aftertreatment system data (DPF regeneration status, SCR efficiency, DEF level), and PTO engagement status. For fleets running heavy trucks, a telematics platform that properly decodes J1939 data for the specific engine makes (Cummins, Detroit Diesel, PACCAR MX) is essential — a platform optimized for light vehicles will miss the data that matters most for heavy fleet operations.
Telematics FAQ
Quick answers to the questions buyers usually ask once the category, software, or rollout details start getting more specific.
A
For light commercial vehicles (vans, pickup trucks, SUVs), OBD-II plug-in devices provide adequate data and are simple to self-install. For medium and heavy-duty vehicles (Class 4–8 trucks), hardwired J1939 connections are required to access meaningful engine and powertrain data. Hardwired installations also eliminate the risk of the device being unplugged and are required for FMCSA-compliant ELD applications.
A
FMCSA-mandated ELDs (Electronic Logging Devices) for commercial drivers subject to HOS regulations must be registered with FMCSA and meet specific technical specifications. Many telematics platforms include ELD functionality as a combined offering, but not all telematics devices meet ELD requirements. If HOS compliance is required, verify the platform is on FMCSA's registered ELD list at eld.fmcsa.dot.gov before purchasing.
A
Active telematics transmits data in real time over a cellular network — this is the standard for modern fleet management, enabling live tracking, real-time alerts, and immediate dispatch visibility. Passive telematics stores data on the device and downloads it when the vehicle returns to a base station or is physically connected. Passive systems are significantly cheaper but provide no real-time visibility, making them suitable only for low-value asset tracking where real-time data is unnecessary.
A
Telematics covers any vehicle data pulled off the engine bus and paired with position. A fleet already collects most of it: hours-of-service duty status recorded by an ELD, engine fault codes and odometer readings broadcast over the SAE J1939 databus, engine hours logged to a tenth of an hour, and latitude/longitude fixes. The FMCSA ELD specification requires exactly this set — power status, motion status, miles driven and engine hours — read directly from the engine ECM (49 CFR Part 395, Appendix A to Subpart B, sections 4.2 and 4.3.1).
A
No. GPS supplies one input: position. Telematics also reads the engine. Under the FMCSA ELD specification, a device fitted to a model-year-2000-or-later truck with an ECM must establish a link to that ECM over serial or CAN and take power status, motion status, miles and engine hours from it, with position handled as a separate channel accurate to within half a mile. A GPS-only tracker cannot produce engine hours or fault codes at all (49 CFR Part 395, Appendix A, sections 4.2(b) and 4.3.1.6(c)).