low batery light on 98 vw beetle

I recently installed a rattler 359d in a 1998 vw beetle,now after 3 days the low battery light comes on just about every time they remote start the car,soon as they put the key in turn it to run and step on the brake and put it in drive and the car rolls about 2 or 3 feet the light goes out, and the car runs fine i caught all the wires and the ign harnes comming right off the stearing coloum,12volts, ign,acc,starter. the only wire i didn't connect was the blue wireit tested kind of weird,12 volts during crank and stays 12 volts after cranking, but has no 12v in the acc and ign possition i was wondering waht would i hook up the blue wire as? aslo would hooking up key sense solve this problem?             

Remote start the vehicle and test the battery voltage. While keeping an eye on the meter, insert the key and take over the car. Did the voltage jump up a volt or so? You might have missed a wire that turn the alternator on.   I remember some older Ford's that acted like that. That blue wire might be it. Do you already have the following hooked up? 12volts      red        +       ignition harness Starter      RED / black        +       ignition harness Ignition      black        +       ignition harness Accessory      BLACK/ red        +       ignition harness

yes j worm i already have all those wires hooked up