Truck diagnostics technology has long played a vital role in maintenance, compliance, and efficiency.
The first on-board diagnostic (OBD) system was invented in the 1980s. Since then, technology has evolved—and innovations branches in diverse directions.
Modern truck drivers might use OBD II systems, European systems, mobile telematics, or a combination of technologies. Different systems’ designs serve diverse functions; they meet changing regulations while, collectively, improving our understanding of our trucks’ inner workings.
With this guide, you can discover how diagnostic technology works and discern the precise ways different systems evolved over time.
This resource explores the benefits and drawbacks of different types of truck diagnostic systems. More importantly, it's designed to help you learn how to use the most advanced diagnostics options to enhance your truck’s health—or even manage your whole fleet.
Get ready to discover the difference smarter diagnostics makes.
What Are Truck Diagnostics Systems?
A truck’s diagnostics system is a monitoring apparatus. It continually observes and assesses the truck’s many systems and parts, then alerts the driver when some part malfunctions or gets damaged.
Typically, to deliver more specific information about the truck parts’ dysfunction, the system must connect with a compatible, external scanner or diagnostic tool.
How Standard Diagnostic Systems Work (Feat. OBD II)
Most contemporary trucks, heavy-duty vehicles, and similar automotives, use an OBD II system for diagnostics.
The OBD II system supplanted earlier diagnostic options: manual assessments, engine manufacturer diagnostics (EBD), and OBD I technology.
OBD II & Alternative Diagnostic Systems, Defined
Here's how The California Air Resources Board (CARB), the first organization to mandate onboard diagnostic systems, describes OBD II:
“OBD II is an acronym for On-Board Diagnostic II, the second generation of on-board self-diagnostic equipment requirements for light- and medium-duty California vehicles.
On-board diagnostic capabilities are incorporated into the hardware and software of a vehicle's on-board computer to monitor virtually every component that can affect emission performance. Each component is checked by a diagnostic routine to verify that it is functioning properly.
If a problem or malfunction is detected, the OBD II system illuminates a warning light on the vehicle instrument panel to alert the driver. This warning light will typically display the phrase "Check Engine" or "Service Engine Soon," and will often include an engine symbol.
The system will also store important information about any detected malfunction so that a repair technician can accurately find and fix the problem.”
— On-Board Diagnostic II (OBD II) Systems Fact Sheet, California Air Resources Board
The Society of Automotive Engineers (SAE) set the technical standard for the OBD II system in 1996.
Contemporary equivalent alternatives to OBD II systems include:
Manufacturer-Specific Diagnostic Protocols
These are typically classified as “OE-Level” diagnostic systems
Most are compatible with the OBD-II standard and exceed it
Mobile (Advanced) Telematics
VAG-COM Diagnostic System (VCDS)
This system is specific to Volkswagen trucks
European On-Board Diagnostics (EOBD)
These systems are standard in the EU
Truck Diagnostic System Parts: Features & Function
While the OBD II isn't the only type of diagnostic system available for commercial vehicles, it uses the same types of components, which serve the same general functions as alternatives. Features include:
Sensors, distributed in a network throughout the truck to scan and transmit data about different parts’ functions
Sensors may also observe environmental factors
Data link components, which transmit the sensors’ information to the onboard computer, and from the computer to external scanning tools
Electric control units (ECUs), one or more onboard computers with:
Hardware, which receives sensor network data
Software, which analyzes the data
Components, which communicate the diagnostic results
All diagnostic systems incorporate those parts in one way or another. However, the specific sensor models’ capabilities, data transmission components, and ECU hardware / software vary from system to system.
Truck Diagnostics’ Evolution: History & Timeline
1960s-1970s: Predecessor Technologies
In these decades, the U.S. government jumpstarted the evolution of telematics technology by launching the first GPS satellite. Meanwhile, Volkswagen created the first on-board diagnostic scanner and computer system for its vehicles, and Datsun comes out with its own version a few years later. By 1979, The Society of Automotive Engineers (SAE) proposes a standardized diagnostic connector and set of diagnostic test signals for all cars and trucks.
1980s: Early Telematics Systems & OBD Prototypes
In 1980, General Motors develops ALDL: the first ever assembly line diagnostic link to utilize a computer, enabling it to read out error codes at scale.
Eight years later, Qualcomm launched OmniTRACS, the first commercial satellite-based mobile communication and tracking system for the trucks. Notably, the OmniTracs system used Ku-Band networks rather than GPS satellites.
1990s: OBD & OBD II Standards
In 1991, The California Air Resources Board (CARB) passed laws mandating all cars and trucks be equipped with onboard diagnostics systems.
These "OBD-I" systems were not nationally standardized; each manufacturer did something different, and external diagnostic tools only worked for one manufacturer.
This changed in 1996, when The Society of Automotive Engineers (SAE) worked with the U.S. EPA to develop the mandatory OBD II Standard.
The new regulations standardized the systems' diagnostic connector design, electrical signal protocols, messaging format, DTC codes, and pinout across manufacturers.
2000s - Present: GPS Fleet Tracking & New Regulations
In 2001, the EU developed the EOBD, the European equivalent of the OBD II. The EOBD was made mandatory for all diesel trucks in Europe in 2003.
In 2005, improvements of machine to machine (M2M) communications led to the development of (and,later, full scale implementation of) comprehensive, GPS-based fleet tracking systems
In 2008, US regulators began requiring all vehicles to implement OBDII through a Controller Area Network (as specified by ISO 15765-4).
Onboard Diagnostics Vs. Advanced Telematics
Onboard diagnostics networks are, typically, closed systems. All data comes from the OBD system’s sensors and the algorithms programmed into the ECU’s software.
In contrast, telematics involves external systems, like GPS satellites. Telematics systems incorporate information from outside sources (like cloud storage platforms, satellite sensors, or external databases), or use analysis protocols of software outside the ECU.
Telematics and OBD technologies can work together to give more accurate diagnostic results.
The Future of Diagnostics & Telematics For Trucks
As technology continues to advance, truck drivers and fleet managers will have more resources than ever to optimize their vehicles. Here's what the next few years—and decades—might look like.
Advanced Telematics Algorithms For Fleet Management
As innovators advance the "internet of things (IoT),” developments of sensor networks, new algorithms, and long-term, granular data storage will lead to better tools for fleet management.
Empowering fleet managers with insights into long term patterns of fuel consumption, dysfunction diagnostic codes, and driver behaviors will improve their ability to optimize decisions—from maintenance schedules to routes.
Mobile Diagnostics With Cloud-Based Platforms
Cloud-based platforms can store more data, and optimize its distribution. As these platforms become ubiquitous, mobile diagnostics will become increasingly fast and more accurate.
Predictive Maintenance AIs
Artificial Intelligence programs can be trained on vast swaths of historic and real time data to.preduct maintenance needs of trucks and fleets. This will empower drivers to minimize downtime and costs with timely, preventative maintenance routines, and maximize time on the road.
Choose The Right Diagnostics System For Your Truck, With Point Spring
Don't let dysfunctional diagnostics keep you off the road. At Point Spring & Driveshaft Co., our certified technicians can help.
Our pros use their decades of combined experience to solve your problems. No matter what your truck's problem is, we solve it right and get you back out on the road fast.
To take advantage of our maintenance, diagnostic, repair, or fabrication services, call 888-787-7746. Or, fill out the form below, and one of our auto professionals will reach out to you.