Overview
ISO 13400-3:2016 - Road vehicles - Diagnostic communication over Internet Protocol (DoIP) - Part 3: Wired vehicle interface based on IEEE 802.3 - defines the physical (layer 1) and data link (layer 2) requirements for IP-based vehicle diagnostics using Ethernet. Focused on 100BASE-TX (and fallback 10BASE-T), the standard specifies how a vehicle’s Ethernet interface (DoIP Edge Node) and external test equipment must be wired, signalled and behaved to ensure reliable DoIP communication.
Key topics and technical requirements
- Physical and data-link baseline: Mandates support for IEEE 802.3 100BASE-TX and backward support for 10BASE-T as a fallback.
- Signal and wiring schematics: Requirements for twisted‑pair link segments, stub lengths and maximum cable lengths to ensure robust operation in automotive environments.
- PHY/MAC and Auto‑Negotiation: Support for Auto‑Negotiation and Auto‑MDI(X) to handle patch vs. cross‑over cable types and link speed negotiation.
- Activation/deactivation lines: Defines activation line behaviour so the DoIP Edge Node Ethernet controller can be enabled/disabled when test equipment is connected or removed; includes two activation-line circuit options and Spice simulation guidance.
- Discovery/identification: Mechanisms for discovery and identification of the in‑vehicle diagnostic Ethernet interface.
- Connector requirements: Mechanical and electrical diagnostic connector specifications, including isolation (1 500 V for 1 min between transformer coils per IEC 60950-1/IEEE 802.3) and identification of two Ethernet pin assignments.
- Compatibility and test equipment: Test equipment interface requirements and recommendations for ensuring interoperability with vehicle implementations.
Practical applications
- Vehicle diagnostics and repair tools (UDS/DoIP) for garages and service centers
- OEM/ECU manufacturers implementing DoIP-capable in‑vehicle gateways and Edge Nodes
- Diagnostic test equipment and interface hardware vendors (cable, connector, PHY design)
- Vehicle software update, calibration and flashing campaigns that require a stable IP-based link
- Conformance labs validating physical/data-link behaviour and activation-line operation
Who should use this standard
- Automotive OEMs and tier‑1 suppliers designing DoIP interfaces
- Diagnostic tool manufacturers and service tool integrators
- Test and validation engineers responsible for vehicle Ethernet interfaces
- Regulatory and homologation teams using standardised diagnostic channels
Related standards
- ISO 13400-1 / ISO 13400-2 (DoIP architecture, transport/network layers)
- ISO 14229 (UDS - unified diagnostic services)
- IEEE 802.3 (Ethernet physical/data‑link specifications)
- IEC 60950-1 (safety / isolation referenced)
Keywords: ISO 13400-3, DoIP, 100BASE-TX, IEEE 802.3, vehicle Ethernet, diagnostic interface, activation line, DoIP Edge Node, Auto-MDI(X), diagnostic connector.