Guide
Remote OBD diagnostics: what it is, how it works and what it can't do
Remote OBD diagnostics means reading, clearing and analyzing a vehicle's faults and data, or programming its ECUs, from a workshop that isn't next to the car. A device in the vehicle's OBD socket carries the communication over the internet to the workshop, and the driver authorizes every session.
Reviewed by Daniel Morales, founder of Reprorace SL, on
How it works with Diaglana
ECO-LITE in the car
It plugs into the OBD socket (SAE J1962), is powered by the vehicle and connects to a Wi-Fi network the driver already has: at home, at the depot or a phone hotspot.
The platform in between
The workshop opens the session from the Diaglana platform, on the web or in the app. The platform records who accesses the vehicle, when and why.
The driver authorizes
ECO-LITE beeps and flashes. A short press of the button authorizes the session; a long press rejects it. Without that press, nothing happens.
The workshop gets to work
It reads and clears faults, watches live data and downloads the report. To use its own tool, it plugs it into the ECO-LITE TOOL on its desk, which reproduces the car's socket.
What can be done remotely
- Read and clear fault codes from every ECU that responds
- Watch live data and record a log during a road test
- Identify the installed ECUs, the VIN and the mileage each one stores
- Check the battery and charging, and get the vehicle ready for its inspection
- Run service functions reviewed and signed by Diaglana
- Code or flash ECUs with your own tool, through ECO-LITE TOOL
What can't be done remotely
- Anything that needs hands on the car: replacing parts, measuring outside the OBD socket or finding a leak
- Calibrations that need targets, alignment or the vehicle on a lift
- Working offline: if ECO-LITE can't reach a known Wi-Fi network, there's no session
- Bypassing your tool's licenses or the manufacturer's protected access
- Guaranteeing that a particular program or make will work: that depends on each one
- Using ECOPRO Gen3: it isn't being manufactured and these pages don't cover it
Driver consent and security
- A physical button
- Every remote session starts when the driver presses the button on the device. The workshop can't get in on its own.
- Every access logged
- Who accessed the vehicle, when and why is kept in the driver's privacy center, and the driver can change workshop from their account.
- Protected identity
- The device's identity is protected in hardware; production units have secure boot and encrypted memory.
- Data under the GDPR
- The driver can download their data or ask for it to be deleted from their account.
Protocols, standards and devices
| Protocol | Standard | J1962 pins | Speed or link | ECO-LITE | ECO-LITE TOOL | ECOPRO Gen4 |
|---|---|---|---|---|---|---|
| CAN | ISO 15765-4 · ISO 11898 | 6 and 14 (2nd channel on 3 and 11; classic CAN on 1 and 9) | 125, 250 and 500 kbit/s | Yes: 2 channels and pins 1/9 | Reproduces the vehicle's | Multichannel |
| CAN FD | ISO 15765 · ISO 11898-1 | 6 and 14; 3 and 11 | Data phase as the vehicle sets it | Yes, on both channels | Reproduces the vehicle's | Multichannel |
| DoIP | ISO 13400 | 3, 11, 12 and 13; activation on 8 | 100BASE-TX (100 Mbit/s) | Yes | Reproduces the vehicle's; Ethernet in PassThru (J2534-2) | Yes |
| K-Line | ISO 9141-2 · ISO 14230 (KWP2000) | 7 | 5-baud or fast initialization | Yes | Reproduces the vehicle's | Yes |
| L-Line | ISO 9141-2 | 15 | Only to start communication | In validation | Not yet | Not stated |
| SW-CAN (GMLAN) | SAE J2411 | 1 | 33.3 and 83.3 kbit/s | Yes | Reproduces the vehicle's | Yes |
| J1939 | SAE J1939 | 6 and 14 or 3 and 11 (the 9-pin connector needs a cable) | 250 and 500 kbit/s | Yes: reading and PassThru | Yes, in PassThru | Not stated |
| PassThru | SAE J2534 · ISO 22900-2 (D-PDU) · TMC RP1210 | Link to the PC, not to the vehicle | USB or network | Basic: J2534 over Wi-Fi | J2534, D-PDU and RP1210 | In development |
Data from the device catalog and the standards cited. The devices are in pre-production: figures may be adjusted after the first units have been validated.
Pre-production: tested on a simulator; validation with vehicles under way. Whether it works with a given program depends on that program: ask us before you buy.
When you need it
- A customer has a warning light on and you want to know whether the car needs to come in
- You run a fleet and want to decide before taking a vehicle off the road
- You're buying or valuing a used car and want to see what its ECUs say
- You need to code or program an ECU and the car is far away
- You work in a network with other workshops or with an expert in another city
Which Diaglana device covers it, and its limits
- ECO-LITE
- Goes in the car. CAN and CAN FD, DoIP, K-Line, SW-CAN and J1939, at 12 and 24 V, over Wi-Fi. Pre-production: first units in validation.
- ECO-LITE TOOL
- Goes on your desk. It reproduces the remote car's OBD socket for your tool and is a pass-thru interface for your PC. Pre-production: remote sessions will open once the remote connection service is in production.
- ECOPRO Gen4
- Workshop station and programming bench, in development. Not on sale yet.
Diagnostic protocols
CAN and CAN FD in diagnostics (ISO 15765)
What CAN and CAN FD are in OBD diagnostics, which pins they use, how fast they run and which Diaglana device reads them remotely, with its limits.
DoIP (ISO 13400): diagnostics over Ethernet
DoIP diagnostics explained for workshops: automotive Ethernet under ISO 13400, OBD socket pins, activation, and which Diaglana device takes it remote.
K-Line and L-Line (ISO 9141-2 / ISO 14230)
What the K-Line and L-Line are, which pins they use, how communication is initialized and what Diaglana does with them in remote diagnostics.
SW-CAN and GMLAN (SAE J2411)
SW-CAN or GMLAN: GM and Opel's single-wire CAN on pin 1 of the OBD socket, its two speeds and how Diaglana covers it in remote diagnostics.
J1939: diagnostics for trucks, buses and machinery
SAE J1939 explained: the CAN of trucks, buses and machinery, its DM1 messages, speeds and pins, and which Diaglana device reads it remotely.
Pass-thru interface: SAE J2534, D-PDU and RP1210
What a J2534 pass-thru interface is, what SAE J2534, D-PDU (ISO 22900-2) and RP1210 are for, and what Diaglana devices offer: real scope and pre-production limits.
Use cases
Fleet remote diagnostics: decide before you take a vehicle off the road
How to use remote diagnostics in a fleet of vans or trucks: what you can see remotely, what you can't, which device you need and how each session is authorized.
Buying a used car: the pre-purchase report from its ECUs
Before you buy a used car, ask its ECUs: the mileage each one stores, faults, recent clears and battery. What the report shows and what it doesn't replace.
Remote diagnostics for trucks and 24 V vehicles
Remote diagnostics for 24 V trucks, buses and vans through the OBD socket: J1939, input protection, cables and what is still in validation.
Remote ECU programming with your own tool
How to code or flash an ECU remotely with your usual tool: ECO-LITE in the car, ECO-LITE TOOL on your desk, requirements and limits.
Workshop networks and remote experts
How a network of workshops and its experts work remotely: shared devices, sessions authorized by the driver, your own brand and verified experts.
Diagnostics glossary
Vehicle diagnostics glossary
Nearly 50 vehicle diagnostics terms explained in a sentence or two: OBD, UDS, DTC, ISO-TP, DoIP, CAN FD, K-Line, J1939, DM1, J2534, D-PDU and more.
OBD fault codes: what each one means
Glossary of OBD-II/EOBD fault codes (P, C, B and U) in plain English: what each code means, common causes, severity and whether you can keep driving.
You may also find useful: Car systems: how they work and what fails Car diagnostics: frequently asked questions For repair shops and professionals: frequently asked questions Will your car pass its MOT or inspection with the engine light on? Wi-Fi OBD2 reader: which one to choose Reading fault codes by car make
Questions drivers ask about this
Shop diagnostics or remote diagnostics: when does each make sense?
An honest comparison: what remote diagnostics solves without moving the car, what still needs a shop visit and how to decide by symptom, with no promises.
Can I diagnose my car myself?
With an OBD reader you can read trouble codes, live data and freeze frame data. What you can do yourself, where the limits are and when to go to a workshop.
Can an OBD reader damage the car or drain the battery?
Reading codes with an OBD reader does not damage the car. The risks are readers that keep the car awake, writing to the control units and security.
Frequently asked questions
What is remote OBD diagnostics?
It's remote vehicle diagnostics through the OBD socket: a device plugged into it carries the communication over the internet to the workshop, which reads faults, watches live data or programs ECUs without the car in front of it.
Can the workshop get into my car without permission?
No. Every session starts when the driver presses the button on ECO-LITE, and it's logged in their privacy center.
Do I need my own diagnostic tool?
Not to read faults, watch live data and get the report: the platform does that with ECO-LITE. To code or program with your usual tool, you also need ECO-LITE TOOL.
Does it work without Wi-Fi in the car?
ECO-LITE connects over 2.4 GHz Wi-Fi and stores up to 5 networks: the driver's home, the depot or the driver's phone. Without any of them, there's no session.
Are the devices on sale yet?
ECO-LITE and ECO-LITE TOOL are in pre-production and sold by reservation order. ECOPRO Gen4 is in development.
Want to try it in your workshop?
Check the device page for the full specifications, or buy in the shop at the final price.