What is a key limitation of using a shorted modular plug during wiring tests?

A key limitation of using a shorted modular plug during wiring tests is that a wiring error may go unidentified. This happens because a shorted plug effectively creates a direct connection between the wires, which can mask issues like crossed pairs or opens. When there is a short, the testing equipment can indicate a successful continuity or connection, leading the technician to incorrectly assume that all wiring is correctly configured when, in fact, there may be faults that the test cannot detect. This limitation highlights the importance of using more comprehensive testing methods to ensure that wiring is both correct and functional.

The other choices, while they describe potential inaccuracies or limitations in testing practices, do not accurately capture the primary concern associated with shorted plugs. For example, voltage readings can be affected by various factors, but the critical issue here is the failure to reveal wiring errors. Similarly, concerns about measuring resistance or testing capabilities may exist, but they are secondary in comparison to the undetected wiring faults that could arise from using such a plug.