Requirements for Built-In Service Port for On Board Diagnostics
This document presents the requirements for a build-in service port to be used in vehicles intended to comply with Enhanced Evaporative Emission Requirements. The primary function of the Service Port (Valve Assembly-Evaporative Emission Canister Purge Harness Service) is to provide non-destructive access to the evaporative emissions system to enable testing of the integrity of the system. The Service Port is used to introduce air pressure or fuel vapors into, or evacuate them out of, the system.
This access may be used for the following evaluations:
Evaporative System Certifications Canister Loading and Pumping
End-of-line Testing System Integrity
Service (e.g. OBD MIL on) Leak Location and Repair Verification
In-Use Compliance Testing Canister Loading and Purging
Inspection/Maintenance Testing System Integrity and Purge Check