Molex Connector Mini-fit 4 pin 0039012040

The Molex Connector Mini-fit 4 pin 0039012040 is a 4-position, 4.20 mm pitch receptacle housing (female socket) with 2 rows. It is designed for free hanging (in-line) mounting and uses crimp termination. The connector is made of polyamide (PA66) nylon 6/6 in natural color and complies with UL 94V-2 and RoHS standards. It is compatible with Molex Mini-fit Jr. 5556 and Mini-fit Plus 45750 series socket contacts.

Parts of this type are selected by matching the number of poles, pitch, and row configuration to the mating connector and wire harness. The mounting style (free hanging, panel mount, or board mount) must correspond to the application. Ensure the contact termination type (crimp, solder, etc.) matches the tooling and wire gauge. Verify the operating temperature range and material compatibility with the environment.

Common failure modes for connectors of this kind include loose or corroded contacts, which can cause intermittent electrical connections, overheating, or complete loss of signal or power. Physical damage to the housing or latches may lead to disconnection. Check for bent or broken pins, signs of arcing or melting, and ensure the connector is fully seated and locked.