40 CFR § 85.2231 - Onboard diagnostic test equipment requirements.
(a) The test system interface to the vehicle shall include a plug that conforms to the requirements and specifications of 40 CFR 86.1806.
(b) The test system shall be capable of communicating with the standard data link connector of vehicles with certified OBD systems.
(c) The test system shall be capable of checking for OBD monitors and the evaluation status of supported monitors (test complete/test not complete) in Mode $01 PID $01, as well as be able to request the DTCs, consistent with the requirements and specifications of 40 CFR 86.1806.
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