ISO 13400-4:2016

Overview

ISO 13400-4:2016 - part of the Road vehicles - Diagnostic communication over Internet Protocol (DoIP) series - defines the Ethernet-based high‑speed data link connector requirements for vehicle diagnostic interfaces. The document specifies a minimum set of connector and electrical requirements for mating connectors used between the vehicle and external test equipment when using DoIP over Ethernet. It builds on the legislated ISO 15031-3 / SAE J1962 diagnostic connector and supports 100Base‑TX Ethernet for diagnostic communication.

Key topics and technical requirements

• Connector functional requirements: Normative specifications for both the vehicle connector and the external test equipment connector, separated into:
  • Connector contact allocation (pin assignments and layouts).
  • Electrical requirements for connectors and related electrical circuits.
• Two Ethernet pin‑assignment options: Option 1 (see Annex A) and Option 2 (see Annex B) provide alternative layouts and pin‑outs to avoid conflicts with vehicle‑manufacturer discretionary pin usage (historically resolving conflicts on pins 1 & 9, or 3 & 11).
• 100Base‑TX (Ethernet) usage: Guidance on Tx+/Tx− and Rx+/Rx− pair placement to support high‑frequency signal integrity and IEEE 802.3 requirements.
• Discovery and activation: The standard references a discovery/identification and activation method using the Ethernet Activation Line (specified in ISO 13400-3) so external test equipment can detect the vehicle’s Ethernet configuration before enabling the electrical Ethernet connection.
• Normative cross‑references: Mandatory references include ISO 13400-1, ISO 13400-3, ISO 15031-3 and SAE J1962 for connector form factor and legislative alignment.

Applications and who uses it

ISO 13400-4 is intended for:

• Vehicle manufacturers designing DoIP‑capable diagnostics and specifying in‑vehicle electrical architecture.
• Diagnostic tool and external test equipment manufacturers implementing compliant connectors, pin‑outs and activation circuits.
• Aftermarket service providers and repair shops that deploy DoIP tools for software updates, calibration, emission testing and manufacturer‑specific diagnostics.
• Regulatory bodies and compliance engineers that reference ISO 15031-3/SAE J1962 mandated connectors and need consistent DoIP implementation across fleets.

Practical benefits include standardized vehicle-to-tool Ethernet connections, reduced risk of electrical damage from incorrect pin usage, and interoperability across diagnostic tools and vehicles.

Related standards

• ISO 13400-1 (DoIP general info and use cases)
• ISO 13400-2 (transport protocol and network layer services)
• ISO 13400-3 (wired vehicle interface based on IEEE 802.3; Ethernet Activation Line)
• ISO 15031-3 / SAE J1962 (diagnostic connector form factor and legislated references)
• ISO 14229 series (UDS diagnostic services)

For implementation details (full pin‑outs, electrical limits and Annex A/B diagrams), consult the complete ISO 13400-4:2016 document.