Not all testing failures are due to bent pins or misplaced wires. Sometimes a wire failure is caused by something as trivial as the zip tie holding the wires in a bundle. These failures are called insulation compression failures and are serious errors that can be avoided.
Insulation is meant to keep wires separate, but with enough pressure the insulation can’t isolate one wire from another. Without sufficient insulation between a wire and another source of metal, the wire will fail during high voltage testing. High voltage failures and compression failures can occur when too much pressure is applied to the insulation around a wire.
If you are experiencing shorts (intermittent or constant) or high voltage testing failures, check if your cables or wires are being compressed with clamps or tight-fitting strain reliefs.
To learn more about compression failures, check out the article in the Cirris Learning Center: