THE CHALLENGEDetached Trailers Are the Blind Spot in Most Fleets
Tractors get all the telematics attention because they have power and a driver. Trailers outnumber them, cost real money, and spend most of their life detached and unpowered in yards and at customer sites, which is exactly where they fall off the radar. Without their own tracker you cannot tell which trailers are loaded, which are sitting idle, when a door was opened, or whether a tyre is going flat. The result is poor utilisation, security gaps, and roadside failures that were avoidable. Trailers need a tracker that powers itself, senses door and load, reads the trailer systems, and reports utilisation, all without depending on a tractor being attached.
A component of the broader Telematics and GPS Tracking capability, often deployed with Asset Tracking Solutions.
WHAT'S INCLUDED
A Tracker Built to Live on the Trailer
Self-Powered Tracker Hardware
The unit is built around a large battery pack with an optional solar panel, a GNSS module with NavIC and GPS, and an LTE modem with Cat-M1 and NB-IoT options. Deep sleep and event-driven wake keep average current tiny so the unit runs for years between service.
Door-Open Detection
A door sensor records exactly when and where a trailer was opened. That gives you security alerts for unauthorized opening and a clean record of delivery and pickup events tied to location and time.
Load and Cargo Sensing
Loaded versus empty is inferred using an air-suspension pressure read, a floor or beam sensor, or an occupancy sensor, picked to suit your trailer build. Knowing load state turns position data into useful dispatch and utilisation insight.
EBS and TPMS Integration
Where the trailer is equipped, the EBS data link is read for brake and ABS events and TPMS tyre pressure and temperature are pulled. You catch a low tyre or a brake fault early instead of at the roadside.
Geofenced Yards and Sites
Yards, depots, and customer locations are geofenced, with every entry and exit timestamped. That is the raw material for dwell time, presence confirmation, and theft detection when a trailer leaves a site it should not.
Utilisation Analytics
Yard dwell, movement, and load state become utilisation, idle-trailer, and turnaround reports. The analytics surface the trailers that are not earning and the sites where they get stuck.
POWER STRATEGY
Years of Life Without a Maintenance Visit
Power is the hardest part of trailer telematics, so it drives the design. The energy budget is modelled against your reporting cadence and sensing needs, then the pack and charging approach are chosen to meet your service interval.
Battery-Only
A large primary or rechargeable pack with aggressive sleep, sized for a few reports a day over multiple years. The simplest option for trailers on a predictable cadence.
Solar-Assisted
A panel tops up a rechargeable pack so the unit can report more often and run more sensing without a service visit. Best for trailers that sit outdoors and need frequent updates.
Tethered Top-Up
When the trailer is connected and the tractor provides power, the unit harvests it to recharge and runs a higher reporting rate, then falls back to its own pack when detached.
The power design draws on the dedicated tracker battery and power management approach, where the energy budget is engineered for long-life trackers.
ARCHITECTURE
From the Trailer to the Platform
On the Trailer
An ultra-low-power MCU under FreeRTOS manages GNSS, sensors, the EBS and TPMS interface, and the radio, waking on schedule or on event. Power management and store-and-forward live here so a detached trailer keeps a record even offline.
Transport
LTE with Cat-M1 or NB-IoT for low-power wide-area coverage carries reports over MQTT, buffering through dead zones. A BLE gate read can confirm presence in deep-cover yards.
Platform
A time-series backend stores position, door, load, and yard events, computes utilisation, and exposes REST APIs and webhooks so trailer data flows into your TMS and fleet platform.
Yard dwell and presence tie into yard management telematics, and the unpowered-asset approach extends the asset tracking work.
STANDARDS AND INTERFACES
Built to the Trailer Ecosystem
EBS and TPMS Interfaces
Standard trailer EBS data links and TPMS sensor sets are supported, so brake, ABS, and tyre data come from the systems the trailer already carries.
Low-Power WAN
Cat-M1 and NB-IoT support keeps the unit reachable on power-efficient networks designed for long-life remote assets, with LTE fallback where needed.
Open Integration
REST APIs and webhooks deliver trailer data into your existing systems, so the trailer fleet is visible alongside tractors and assets rather than in isolation.
FAQ
Common Questions
How does a trailer tracker run without vehicle power?
A trailer spends long stretches detached from any tractor, so the unit is designed to power itself. The core runs from a large primary or rechargeable battery sized for years of life at a reporting cadence you set, and a solar panel option tops up the pack so the unit can report more often without a maintenance visit. Aggressive sleep modes and event-driven wake keep average current in the microamp-to-milliamp range between reports.
How long does the battery last?
It depends on reporting frequency and whether solar is fitted. A battery-only unit reporting a few positions a day can run for years, while a unit reporting frequently or doing a lot of sensing draws more. The budget is modelled against your duty cycle and the pack sized accordingly, and the solar option extends life substantially for trailers that sit outdoors.
What door and load sensing is available?
A door-open sensor records exactly when and where a trailer was opened, which matters for security and for delivery confirmation. For load state, cargo sensors such as an air-suspension pressure read to infer loaded versus empty, a floor or beam sensor, or a simple occupancy sensor are options, chosen to fit how your trailers are built and what you need to know.
Can it read EBS and TPMS data?
Yes, where the trailer is equipped. The unit interfaces to the trailer EBS over its data link to pull brake and ABS event data, and reads TPMS sensors for tyre pressure and temperature. That turns the tracker from a position dot into a source of maintenance and safety signals, so you catch a low tyre or a brake fault before it becomes a roadside breakdown.
How do geofenced yards and utilisation work together?
Yards, depots, and customer sites are geofenced. Every entry and exit is timestamped, so the system knows how long each trailer sat in each yard versus how long it was on the road. From that, utilisation, dwell, and idle-trailer reports are computed, which is what exposes the trailers that are quietly sitting unused and the yards where trailers pile up.
How do untethered trailers stay visible if they go to remote sites?
The unit reports over LTE with Cat-M1 or NB-IoT options for low-power wide-area coverage, and it buffers positions when there is no signal and forwards them when coverage returns. For deep-cover yards a BLE gateway read at the gate can confirm presence even when the cellular link is marginal, so a trailer does not simply go dark.
Does this integrate with your existing fleet system?
Yes. Trailer position, door, load, and yard events flow into the same backend over MQTT and out through REST APIs and webhooks, so trailer data sits alongside your tractor and asset data rather than in a separate silo. The feed is mapped to your TMS or fleet platform during integration.
Ready to Bring Your Trailers Online?
Share your trailer count, how they are built, and how long they sit detached to get a tailored power sizing, sensor selection, and analytics scope so every trailer reports for itself.
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