Xbox in a Corolla

Hi, I am trying to install my Xbox into my 2004 Corolla S with the Pioneer 5700 Headunit, i got a 400watt inverter attached to the battery turned it on, plugged the xbox in, and I get lines across the screen like there is interference, I then took an extension cord plugged the xbox into my house outlet and the lines went away, so I think it has something to do with the inverter, there is no place to put a ground wire on the inverter so im running out of ideas as to what to do. anyone think they know the problem?

First, What is the Make and model of your inverter? You mean your inverter only has 1 terminal to run a wire to? All inverters I have seen have 2 posts, one for positive and one for negative. Does it have a special cable that llets you plug into a cigarette lighter outlet? if so, there will be 2 separate wires in that cable which you could cut to wire it directly to the battery and ground.

I have a 400 watt vector unit and I have not had lines in anything that I have used it for and I tried my 25 inch TV on it. The inexpensive inverters are called modifed sine wave inverters. The Vector is one of these. The modified sine wave inverters work fine for most things. If you cant solve your problem by hard wiring it in (assumuing that you havent), you can get a small pure sine wave inverter. These are a little more expensive, but they do a better job of mimicing what the power company sends to your home. They cause power bricks to run cooler, motors to run better and avoid lines in tv screens. Do a quick google search for pure sine wave inverters. They are easy to comeby and a 400 watt runs about $150 if I remember correctly.

I had a Playstation in the truck I used to own.  I didnt get any video interference, but I did get a lot of audio interference from my power inverter.  I tried plugging it into an extension cable to a house outlet like you did and it was all fine.  I checked the ground and sanded down to the bare metal around the grounding screw I was using and it worked fine after that. Maybe you have a bad ground?  If its the inverter that plugs into the cigaratte lighter, you might be better off hard wiring it.