These modules are for use on GM vehicles equipped with a 2 pin regulator and a RVC sensor (Regulated Voltage Control). Simply plug module into your vehicle's factory harness and tie out of the way. This will eliminate the check charging system code (battery light).
These are especially popular for the customer who wants to bypass the RVC system so that they can run a stand-alone alternator. The reason for this is that when run in the factory form on these model vehicles there will be fluctuating voltage and normally they will charge at a lower voltage. Although this is all normal since the PCM is controlling the voltage in order to acquire max fuel economy, some will opt to go with a stand-alone unit to acquire a higher and more stable voltage.
Keep in mind this does not work with the factory alternator. You will need to purchase a special ordered unit that is built with single ignition switched turn on. Just order the alternator for your application as you normally would and specify in the notes that it needs to be single wire turn on. If you already have the correct alternator and just need the plug, you will need to purchase the P101 as well. See SKU# P101 for more details.