本规范定义了无焊压接连接验证的测试方法和要求。该测试的目的是在实验室中模拟压接连接在典型寿命（15年和150000英里）中看到的应力，并确保压接具有机械强度和电气稳定性。本规范是为汽车铜线绞合而制定的。仅在特别提及的情况下，其他结构或其他芯材料（铝、包层、钢芯等）。）适用。本规范不适用于未提及的电线类型，如同轴电缆压接，除非该电线类型的测试规范中特别提到了USCAR-21测试。 本规范基于可接受的汽车应用环境暴露水平。在任何预期的车辆应用中，如果本说明书所涵盖的产品正在或可能经受超出本文所述条件的条件，则它们必须通过模拟实际遇到的条件的特殊测试，然后才能被认为可用于实际车辆应用。经其供应商证明已通过本规范特定适用部分的产品不得用于条件可能超过产品已令人满意测试条件的应用中。任何偏差必须记录在案并包含在最终测试报告中。 根据本规范验证的压接应用旨在取代组件打印件上的压接信息。端子供应商主要负责测试和选择压接工具，并向实际进行生产压接的布线组件供应商提供详细的压接信息或提供压接工具。线束供应商负责验证按照本规范生产的所有压接。 本规范中提到的环境暴露包括热冲击和温度湿度循环，用于对测试中使用的每个生产端子和电缆组合施加应力，以模拟现场暴露。SAE/USCAR-21的测试将检测压接工具几何形状、电镀质量、绞线分布和电缆绞线数量方面的缺陷。除了连接器系统验证（如SAE/USCAR-2）之外，还必须进行SAE/USCAR-21，以确保每个组合的整个允许生产压接高度范围是可接受的。对连接器系统规范的测试也验证了SAE/USCAR-21中未测试的内容，如长期高温暴露。 本规范中包含的程序旨在涵盖作为低压电气连接系统一部分的电气端子压接的性能测试和开发（0至48 VDC）环境温度最高为125°C的道路车辆应用。如果OEM客户批准在超过这些限制的电压和温度下使用这些测试程序，则可以测试更高的电压和温度。

This specification defines test methods and requirements for validation of solderless crimped connections. The purpose of this test is to simulate in the lab the stress seen in a typical life (15 years and 150000 miles) for a crimp connection and assure the crimp is mechanically strong and electrically stable. This specification was developed for use with stranded automotive copper wire. Only where specifically mentioned are other constructions or other core materials (aluminum, clad, steel core, etc.) applicable. This specification does not apply to wire types not mentioned, such as coaxial cable crimps, unless a USCAR-21 test is specifically referenced in the test specification for that wire type. This specification is based on accepted levels of environmental exposure for automotive applications. In any intended vehicle application, if the products covered by this specification are or may be subjected to conditions beyond those described in this document, they must pass special tests simulating the actual conditions to be encountered before they can be considered acceptable for actual vehicle application. Products certified by their supplier as having passed specific applicable portions of this specification are not to be used in applications where conditions may exceed those for which the product has been satisfactorily tested. Any deviation must be documented and included in the final test report. Crimp applications validated to this specification are intended to supersede crimp information on the component prints. The terminal supplier has the primary responsibility for testing and selection of crimp tooling and to supply detailed crimp information or make crimp tooling available to the wiring assembly supplier actually doing the production crimping. The wiring harness supplier is responsible for validating all crimps produced per this specification. Environmental exposures called-out in this specification include Thermal Shock and Temperature Humidity Cycling and are used to stress every production terminal and cable combination used under test to simulate field exposure. SAE/USCAR-21 has tests that will detect deficiencies in crimp tooling geometry, plating quality, strand distribution, and cable strand count. SAE/USCAR-21 must be done in addition to a connector system validation such as SAE/USCAR-2 to assure the entire allowable production crimp height range of every combination is acceptable. Testing to a connector system specification also validates what is not tested in SAE/USCAR-21 such as long-term high temperature exposure. Procedures included within this specification are intended to cover performance testing and development of electrical terminal crimps that are part of the electrical connection systems in low voltage (0 to 48 VDC) road vehicle applications at ambient temperatures of 125 °C maximum. Higher voltages and temperatures may be tested if the OEM customer approves use of these test procedures for use at voltages and temperatures beyond these limits.