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The Pennsylvania Code website reflects the Pennsylvania Code changes effective through 52 Pa.B. 3204 (May 28, 2022).

67 Pa. Code § 177.203. Test procedures.

§ 177.203. Test procedures.

 (a)  I/M emission test procedures.

   (1)  Idle testing. Idle tests of all model year subject vehicles shall be performed in accordance with the procedures in 40 CFR Part 51, Subpart S, Appendix B(I) and (II) (relating to test procedures-idle tests) which is adopted by reference, and Appendix A (relating to simulation mode: Pennsylvania procedures, standards, equipment specifications and quality control requirements). The following steps shall be taken when testing subject vehicles:

     (i)   Emission test data shall be entered into the analyzer by a certified emission inspection inspector using the bar coded vehicle registration card or the alpha-numeric keyboard in the sequence specified.

     (ii)   Idle tests shall be either one-speed or two speed as specified in §  177.51(f) (relating to program requirements).

   (2)  ASM test. The ASM test of 1981 and newer model year subject vehicles shall be performed in accordance with the ASM test procedure and specifications and quality assurance requirements contained in Appendix A. The ASM test procedure, including algorithms and other procedural details, shall be approved by the EPA prior to use in the I/M program of the Commonwealth. Special test algorithms and pass/fail algorithms may be employed to reduce test time when the test outcome is predictable with near certainty, if approved by the EPA.

   (3)  Evaporative system function tests. Evaporative system functions tests, including an evaporative system pressure test and an evaporative system purge test on 1981 and newer model year subject vehicles, shall be administered on subject vehicles registered in Bucks, Chester, Delaware, Montgomery and Philadelphia counties upon notification to the Department of EPA approved procedures and will be conducted based on the procedures approved by the Department.

 (b)  OBD-I/M check.

   (1)  Readiness requirement for a valid OBD-I/M check. An initial scan of the OBD system should determine the status of all readiness codes.

     (i)   A status indication of ‘‘not ready,’’ ‘‘not supported’’ or similar message for one or more of the continuous monitors (that is, misfire, fuel trim or comprehensive components), may be disregarded for readiness determination purposes only and the OBD-I/M check can proceed.

     (ii)   For model year 1996—2000 vehicles, a status indication of ‘‘not ready,’’ ‘‘not supported’’ or similar message for two or fewer other readiness codes may be disregarded for readiness determination purposes only and the OBD-I/M check can proceed.

     (iii)   For model year 2001 and newer vehicles, a status indication of ‘‘not ready’’ or ‘‘not supported’’ for no more than one other readiness code may be disregarded for readiness determination purposes only and the OBD-I/M check can proceed.

     (iv)   The readiness requirement may also be waived or otherwise accommodated for specific makes, models, and model years of vehicles with known readiness design problems, in accordance with applicable technical service bulletins or EPA guidance, or both. The Bureau will advise all participating stations by station bulletin whether the readiness requirements can be waived or otherwise accommodated for specific makes, models and model years of vehicles.

   (2)  Performing the OBD-I/M check. Following a determination of readiness, the seven step procedure delineated below shall be used when performing an OBD-I/M check:

     (i)   Initiate the official test by scanning or manually inputting the required vehicle and owner information.

     (ii)   Visually examine the vehicle instrument panel to determine if the MIL illuminates briefly when the ignition key is turned to the ‘‘key on, engine off’’ (KOEO) position. A brief period of illumination of the MIL at start-up is normal and helps confirm the MIL bulb is in proper operating condition. This portion of the test procedure is also known as the ‘‘bulb check.’’ Enter the results of the bulb check for downloading into the VIID.

     (iii)   Locate the vehicle’s data link connector (DLC) and plug the scan tool into the connector. While it is recommended that this step be performed with the ignition in the ‘‘off’’ position, this step can also be performed with the vehicle running.

     (iv)   Start the vehicle’s engine so that the vehicle is in the ‘‘key on, engine running’’ (KOER) condition. The MIL may illuminate and then extinguish during this phase. Continued illumination of the MIL (MIL commanded on) while the engine is running is cause for failure of the OBD-I/M check under §  177.204(2) (relating to basis for failure).

     (v)   With the scan tool in the ‘‘generic OBD’’ mode, follow the scan tool manufacturer’s instructions to determine vehicle readiness status, MIL status (whether commanded on or off), and diagnostic trouble codes (DTCs) for those vehicles with the MIL commanded on.

     (vi)   The results of the OBD-I/M check will be transferred automatically to the VIID.

     (vii)   Without clearing DTCs or readiness codes, turn off the vehicle ignition and then disconnect the scan tool. Procedure for clearing codes as necessary is included in §  177.271 (relating to procedure).

 (c)  Gas cap test procedures. The gas cap test will be conducted using test equipment approved by the Department, in accordance with the manufacturer’s instructions.

 (d)  Visual inspection procedures.

   (1)  A visual inspection of the vehicle emission control system shall look for the presence of the following emission control devices:

     (i)   Catalytic converter.

     (ii)   Exhaust gas recirculation (EGR) valve.

     (iii)   Positive crankcase ventilation (PCV) valve.

     (iv)   Fuel inlet restrictor.

     (v)   Air pump.

     (vi)   Evaporative control system components.

   (2)  Visual inspections shall be performed through direct observation or through indirect observation, using a mirror or other visual aid.

   (3)  Inspections shall include a determination as to whether each subject device is present and appears to be properly connected and to be the correct type for the certified configuration.

 (e)  Subsequent test procedures approved by the EPA. If the EPA develops or approves other test procedures, including test procedures prescribed in this section, the Department may adopt these subsequently approved test procedures consistent with section 4706(e) of the Vehicle Code (relating to prohibition on expenditures for emission inspection program).


   The provisions of this §  177.203 amended November 21, 2003, effective November 22, 2003, 33 Pa.B. 5706. Immediately preceding text appears at serial pages (235268) to (235269).

Cross References

   This section cited in 67 Pa. Code §  177.3 (relating to definitions); 67 Pa. Code §  177.51 (relating to program requirements); 67 Pa. Code §  177.204 (relating to basis for failure); 67 Pa. Code §  177.271 (relating to procedures); and 67 Pa. Code §  177.408 (relating to certified emission inspectors).

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