First identify whether the code is an FMCSA malfunction/diagnostic event, an HOS violation, an inspection-system code, or a vendor message.
What this means for your fleet
Build a code-resolution sheet with four fields: exact code and screen, issuing system, driver and vehicle context, and authoritative source. Preserve screenshots before clearing or restarting anything.
First classify the code
| What the screen or report shows | Category | Where to check |
|---|---|---|
| Power, engine synchronization, timing, positioning, data recording, transfer, or unidentified-driving indicator | ELD diagnostic or malfunction class | Installed-device manual plus FMCSA malfunction guidance |
| Driving beyond an HOS limit or missing required rest | HOS exception or violation analysis | Current 49 CFR Part 395 rule and carrier compliance review |
| Roadside inspection or enforcement-system code | Inspection result | Inspection report and issuing authority |
| Vendor-only alert or error message | Product support event | Exact provider documentation and support ticket |
What to check
| Check | How to verify |
|---|---|
| 1. Capture the exact code and wording | Capture the exact code and wording, icon or report, screenshot, date/time, driver, vehicle, device/app versions, and affected function before restart. |
| 2. Identify the issuing system | Retain the product, ELD event detail, inspection report, HOS screen, or vendor system that issued it, plus source identifier and owner. |
| 3. Check event time and vehicle | Keep event time, vehicle/VIN, driver, duty record, operating context, surrounding events, location, assignment, and preserved original. |
| 4. Separate HOS from device health | Classify the item against the current HOS provision, ELD malfunction/diagnostic definitions, inspection report, or vendor manual; record reviewer and result. |
| 5. Use the official guidance or device manual | Save the exact authoritative guidance or installed manual section, required response, notice or repair path, completed action, cleared result, and retest. |
Common failure modes
- Relying on a code list that does not identify the device or inspection system.
- Confusing warnings with citations.
- Restarting before evidence capture.
Limits and exceptions
Use this guide to plan your checks; it does not determine whether a legal exception applies, certify a record, or guarantee compliance, safety, savings, or audit results. Preserve original ELD records and edit history. Use the current rules to determine applicability and the manual for your installed device for operating instructions.
Factor device codes are not inspection violation codes
The Factor PT30 registry entry uses letters for malfunction classes and numbers for diagnostic events. These are device indicators; an officer’s inspection report uses its own violation references.
- P / E / T / L: power, engine synchronization, timing and positioning malfunctions.
- R / S / O: data recording, data transfer and other ELD malfunctions.
- 1 / 2 / 3: power, engine synchronization and missing-required-data diagnostic events.
- 4 / 5 / 6: data transfer, unidentified driving and other diagnostic events.
For example, diagnostic 5 points to unidentified driving records. It does not by itself identify a citation or prove a driver’s HOS violation. Preserve the full displayed message and use the exact model’s instructions. The code class alone is not a repair procedure.
Sources
Sources and review date
Reviewed August 10, 2026. Check the latest rules and product information before changing your procedures or signing a contract.
- ELD malfunction and data-diagnostic responsibilities — Federal Motor Carrier Safety Administration.
- Roadside and safety-official ELD data-transfer methods — Federal Motor Carrier Safety Administration.
- 49 CFR Part 395: hours of service and ELD requirements — Office of the Federal Register and U.S. Government Publishing Office.
- Factor ELD products, plans, and support — Factor ELD.