When inspecting your connectors be sure that they are screwed flush against each other. Here is the example for the connections that go from your handlebar items to your 4-1 wire harness
Inspections are recommended because the partial connection might work but issues like moisture condensation and connector wear can happen down the line.
Be sure to always push and pull from the connector itself, never from the cable. And to use both sides of the screw connector to undo/redo the connection. Also is good to give the connectors a push after screwed