The DRL module can be wired so that both left and right lamps are synchronized. In other words, when in DRL mode, if you turn on a signal, the other lamp turns off. After the signal is complete, both lamps come back on in DRL mode. The reason this is done is because there can be a situation if an oncoming driver just glances at your car while you have a signal on. If he looks when the turn signal is in the off cycle, he will see the other lamp on, and may assume you are turning the other way. In synchronized mode, the other lamp turns off, so there is no confusion.
In non-synchronized mode, the opposite lamp will stay in DRL mode when a turn signal is in use. This is the way turn signal DRLs operate on today's automobiles. You can program the DRL module to work in synchronized or non-synchronized mode. As you receive the module, it is programmed in non-synchronized mode. If you want this mode, then you can skip this section and continue with the installation.
If you want the unit to operate in synchronized mode, use a quick-splice to connect the white wire to the green module wire. This is not a permanent setting. If you later wish to go back to non-synchronized mode, simply disconnect the two wires.