Unsure of what this connector is for

[RustRatz]

Found 4 pin connector on same wiring that goes to alternator. Unsure of what it does.
Wire colors are yellow/white, black, black/yellow, green/red.

 

[franklin2]

Is your alternator stock? Has it been re-wired? Those colors sound like the alternator wiring colors. You would think if it was unplugged it would not be charging.

 

[RustRatz]

Is your alternator stock? Has it been re-wired? Those colors sound like the alternator wiring colors. You would think if it was unplugged it would not be charging.

It’s stock. I just don’t know what this connector goes to.

 

[RonD]

Light Green/red and Yellow/white were used on alternator's 3 wire plug, but not Black or Black/yellow

O2 sensors were 4 wire and had a round connector

 

[RustRatz]

Light Green/red and Yellow/white were used on alternator's 3 wire plug, but not Black or Black/yellow

O2 sensors were 4 wire and had a round connector

O2 sensor is plugged in, so I’m not entirely sure of what this is for. If it’s nothing important, I’ll get a dummy plug for it, just so I know it’s not in use.