The plastic retention tabs that hold the wiring harness connector in place are easily broken. Once broken, the connector may push into the case.
This metal bracket positively supports the connector and prevents it from pushing into the case even if the plastic retention tabs are broken.
It is common for one of the three plastic retention tabs to break on the wiring harness case pass-through connector. This allows the connector to be pushed into the case when connecting the external harness. Not only does this require extra labor to fix, it also requires a new wiring harness. Sonnax has now developed two wiring harness connector brackets to retain the internal harness connector even though the retention tabs may be broken: 77980-01K for the 4L60-E, and 34998-01K for 4L80-E units with late-style gray connectors only.