Amended Phase 2a Worldwide Light vehicles emissions Test Procedure (WLTP). Versions of the amended GTR highlighting the changes to the original regulation are available in word format and pdf format. The amendments address:

1. If an alternative value is applied for a parameter, such as a higher n_min_drive or an ASM, this parameter value has to be the same within an interpolation family (Paragraph 5.6.1.).
2. The mass in running order used for the calculation of the power to mass ratio is replaced by mass in running order minus 75 kg (paragraph 1. of Annex 1).
3. Idle engine speed n_idle is removed from the power curve measurement requirement (paragraph 2. of Annex 2).
4. The additional safety margin (ASM) value may be decided by manufacturer rather than the prescribed exponential curve (paragraph 3.4. of Annex 4).
5. The number of decimal place of road load coefficients is defined (paragraph 2.4. of Annex 4).
6. Additional restrictions are set to the application of the split run method for coastdown testing (paragraph 4.3.1.3.4. of Annex 4).
7. Specific data rejection criteria are added (paragraph 4.3.1.4.3. of Annex 4).
8. The “delta method” for road load determination is added (paragraph 6.8. of Annex 4 and other paragraphs. See section 4.4.25.for more detail).
9. The roller radius correction factor is modified(paragraph 6.6.3. of Annex 4).
10. The allowable combination of the test vehicle selection and family requirements are further clarified (paragraph 4.2.1.3. of Annex 4 and other paragraphs of Annex 4).
11. Provisions for an additional cooling fan are included(paragraph 1.1.5. and 1.1.6. of Annex 5).
12. The correction of measurement/recording frequency requirements are specified (over several annexes).
13. Calculation of the n/v ratio is defined (paragraph 8. of Annex 7).
14. The stepwise procedure for calculating the final test results of OVC-HEVs is added (paragraph 4.6. of Annex 8).

Proposal to allow the use of compliance assessments of vehicles with a reference mass less than 2,610 kg in extending the type approval to special purpose vehicles (including armoured ones) having a reference mass exceeding 2,840 kg. This proposal would align UN R83 with provisions of European Directive 2007/46/EC.

Text prepared by the Evaporative emissions Task Force of the WLTP informal working group in line with Phase 2 of its mandate (ECE/TRANS/WP.29/AC.3/44). The WLTP referred to a first draft of this proposal (GRPE-73-12) at the seventy-third session of GRPE (see report ECE/TRANS/WP.29/GRPE/73, para. 12).

During the June 2016 GRPE session, AEGPL raised concerns regarding the back-to-back approach for the simplified test of retrofitted dual-fuel engines because, in some cases, the hydrocarbons (HC) and/or carbon monoxide (CO) emission values of the original diesel engine are far below the emission limit (see GRPE-73 session report, para. 28). AEGPL proposed a solution in document GRPE-73-07. However the Netherlands is concerned that:

1. The emission performance of the selected diesel engine is not known (above or below the emission limit and how far from the limit);
2. Non-methane hydrocarbons (NMHC) emission cannot be disregarded because NMHC is an important air quality regulated pollutant emission; and
3. The diesel emissions of CO and HC could be far below the emission limit and hence a factor of two would not be sufficient while increasing this factor is problematic.

Contracting Parties and stakeholders have discussed a solution, presented in this proposal, to compare measured emissions of a retrofitted dual-fuel engine with the brake specific emission limits using a CO2 specific emissions approach. This proposal would amend the draft regulation pending before WP.29 (document WP.29/2016/110).

Proposal to adapt the 06 and 07 series of amendments to Regulation No. 83 to Selective Catalytic Reduction (SCR) warning and inducement systems to current vehicles, emissions requirements and reagent infrastructure. In light of further vehicle weight reduction for CO2 optimization and the resultant vehicle packaging challenges, diesel cars will likely have smaller AdBlue® reagent tanks. For passenger cars, the warning indicator to refill AdBlue® has to be activated at 2,400 km of remaining reagent range which could result in very frequent refills of smaller reagent tanks. This proposal would allow for reagent refill inducement warnings as a percentage of tank capacity. For heavy-duty vehicles, the warning has to be activated at least at a reagent level of 10 per cent of total reagent tank volume. The inducement system has to be activated at least at 2.5 per cent of reagent level.

Proposal to introduce provisions to align UN R49 with recently introduced stage D EU legislation in order enable manufacturers to continue to utilize the provisions in paragraph 4 of Annex 9A to approve light commercial vehicles with a light duty OBD architecture under this regulation. This proposal incorporates all of the provisions of the latest amendment to EU legislation. As stage D is unrelated to OBD, the proposal is to make stage C and all subsequent stages equivalent to EOBD 6-2.