Console will not work with AV cable

I'm trying to get my Xbox 360 to work, it will only display through HDMI, which I cannot use because I use the HDMI cord for my PS3, so I'm using the cable that came with the xbox, all 3 prongs are in the right place, TV is on the right input.

I also tried to reset my display settings by doing that thing where you hold Y and RT, it did nothing, the console didn't even restart.

I tried looking through the settings trying to find a way to manually switch outputs, can't find anything.

Buying another HDMI cord is not an option, I just wanted to play some Forza 4, not going to spend any money just for 1 game.

:)

 

HDMI TO SCART/COMPONENT

All AV cables are compatible with all 360 consoles. The older SCART/Component 360 AV cables will work fine with a 360 S.

 

Console won't start???

Unless I have missed something it doesn't seem that you have tried changing over the AV cables for the console. Could you try using your son's AV cables on your Xbox and your AV cables on his Xbox just to check that the cables do or do not work.

 

There are many possibilities for this to happen:

Internal Breakages

As with any other audio/video cable, the AV cable of the Xbox 360 can become broken. If the console is frequently moved (due to console rentals, LAN parties etc), the cable can be placed under extra stress. Winding the cable too tightly--to fit it into a
bag for transportation, or to tidy it out of the way for a cleaner TV area--can place internal stress on the cable, snapping the wires within and rendering the cable non-functional. Internal stress can also be caused by stretching the cable too tight, such
as when the console is placed too far from the television.

Frayed Cables

Even if the cable's insulation is broken but the inner wires seem undamaged, a replacement or repair should be sought. Cable insulation can be damaged during un-packaging, or if heavy furniture or appliances are placed on top of the cable.

The TV/HDTV Switch

Many Xbox 360 cable problems are caused by an improperly set TV/HDTV switch. This switch, located near the end where the cable connects to a television, enables the user to switch between regular and HD (High Definition) picture output from the cable. However,
this isn't the only step in setting your Xbox 360 to high-def output. This setting must be chosen in your console's menu as well: go to the "Console Settings" section of the Xbox 360 user menu and choose "Display." Choose between regular and HD output, then
reset your console and change the AV cable's switch to the desired position.

Check your AV cable integrity and order another replacement if need be!