2005 Chevy Malibu Remote Start-What remote start keypass module do I need?

[dave w]

2005 Chevy Malibu (Not Classic). I am installing an aftermarket remote start but cant find anywhere what passlock version I need. I have a 555G but I think I read somewhere that I need a 556U instead. Can anyone provide a link to a chart that shows? Ive tried google and calling the deal and still cant figure it out.
The key does not have a PK inscription anywhere on it. It does have a + sign on both sides of the metal on the key
Forgot to add though that there is not a circle around the + sign

 

[KaeZoo]

If your key has PK3 or a + sign in a circle stamped on it, then the 556U will work for you. You'll have to install one of your keys into the 556U module, so if you don't have a spare, you'll need to have one made.

Edit: The + is probably enough. According to my information, your vehicle is equipped with the PassKey3+ system. The 556U should work for this, although in most PK3+ cars there's also a resistance built into the key switch as part of the anti-theft system. There doesn't seem to be anything of that sort on your Malibu. If you don't want to give up a key, there are other modules available that will bypass your anti-theft system without the spare key. http://www.autoalarmpro.com/gm They require a bit more work to install, though.