Common automotive electrical connectors include butt, ring terminal, quick disconnect and closed-end automotive wire connectors. Butt connectors, the most common crimp-style connectors, make end-to-end connections between two wires, while a ring terminal, another common crimp connector, is useful for terminating a wire at a connection point, such as a bolt on the rear of an alternator. The spade terminal, another type of crimp connection, also allows this, but without requiring the bolt to be removed.
Quick disconnect connectors are useful for removable switches or lights in a dash panel. There are two types of quick disconnect connectors, bullet and push-on, both available in male and female versions. These connectors are suitable for low-current use under the hood. Closed-end connectors are similar to twist lock connectors and sized according to wire gauge.
Automotive connectors either come with a vinyl or nylon insulation on top of the connector or are non-insulated and require insulation after crimping. Connector insulation is either straight or flared at the end, which typically fit better. Some insulated connectors feature heat-shrinkable insulation that provides a weather-tight connection. These connectors contain an active adhesive that, when heated, can seal multiple wires and reduce wire pull-out.
Manufacturers of these and other automotive electrical connectors include Dorman, available at AutoZone, Waytek, available at WaytekWire.com, and Metri-Pack and Weather Pack from WhiteProducts.com.