OBD-II ELD: What It Is and How to Pick the Right One
The simplest way to make a truck FMCSA-compliant — no wiring, no mechanic.
An OBD-II ELD is an Electronic Logging Device that plugs into your truck's diagnostic port instead of being hard-wired. It's what most small fleets and owner-operators use because installation takes minutes, not hours. ELD Hub ships two FMCSA-registered OBD-II devices — the PT-30 and IOSiX — bundled into $15/truck/month with no contract.
OBD-II ELD at a glance
| What it is | Plug-in Electronic Logging Device for the OBD-II port |
| FMCSA rule | 49 CFR 395.15 — must be on the FMCSA ELD list |
| Install | Plug in, pair Bluetooth, log in — under 10 minutes |
| Devices ELD Hub ships | PT-30 and IOSiX (both FMCSA-registered) |
| Best for | 1–20 truck fleets and owner-operators |
| Price | $15/truck/month with ELD Hub — device included |
- No wiring, no mechanic, no ECM programming — plug in and drive.
- Reads engine miles, engine hours, speed, and RPM through the diagnostic port.
- Automatically detects duty status changes (Driving, On Duty, Off Duty, Sleeper).
- Pairs to the driver's phone or tablet over Bluetooth.
- Both PT-30 and IOSiX OBD-II devices work with ELD Hub — pick either.
- Passes DOT roadside inspection in every state.
Frequently asked questions
Are OBD-II ELDs FMCSA-compliant?
Only if the specific device is on the FMCSA ELD registration list. Both the PT-30 and IOSiX (the two OBD-II ELDs ELD Hub ships) are registered. Not every device sold as 'ELD' on Amazon or eBay is on the list — check the FMCSA list before buying.
What's the difference between an OBD-II ELD and a hard-wired ELD?
OBD-II ELDs plug into the standard diagnostic port under the dash — no tools, no mechanic, driver can install it in 5 minutes. Hard-wired ELDs (older 9-pin/6-pin models on heavy-duty trucks) tap directly into the engine wiring. Both are FMCSA-compliant. OBD-II is easier and cheaper for 1–20 truck fleets.
Which OBD-II ELD should I buy — PT-30 or IOSiX?
Both are FMCSA-registered and both work with ELD Hub. The PT-30 is the cheaper, more common option and covers most Class 3–8 trucks. IOSiX has slightly cleaner data on 2020+ model-year trucks. When you sign up with ELD Hub, tell us your truck year/make/model and we'll pick the right one.
Can I use any OBD-II adapter as an ELD?
No. A generic OBD-II scanner or Bluetooth dongle is not an ELD. To be legal for HOS logging under 49 CFR 395, the device must be on the FMCSA ELD registration list and paired with a compliant app. That's why we ship registered PT-30 and IOSiX devices rather than generic adapters.
Does an OBD-II ELD work on heavy-duty trucks?
Yes, but you need the right cable. Class 7–8 trucks use a 6-pin or 9-pin round diagnostic connector instead of the flat OBD-II connector on light-duty vehicles. ELD Hub ships the correct cable based on your truck's year and make at no extra charge.
How much does an OBD-II ELD cost per month?
With ELD Hub, an FMCSA-registered OBD-II ELD device (either PT-30 or IOSiX) plus the HOS software, DVIRs, IFTA, and dispatcher dashboard is $15/truck/month with no contract. Most competitors charge $25–50/truck/mo with a 1–3 year contract.