You need to start from scratch as regardless of whether she was housetrained at one point, she isn't any more. You need to begin again (the good news is that because she did have some of the idea on what to do, it should go much faster). You probably made the same mistake so many of us do (as this is such a common problem!)-- assuming she was housetrained before she was and thus stopped watching her and remaining with her and let her have open access to the house, or part of the house, without supervision. Thus she likely began to do small wees -- when younger these can be tiny and hard to spot but over time she has left urine everywhere which to her, signals a place she should return to to go (we take advantage of this instinct to housetrain by getting them to go in the same place outside as a puppy -- but it works both ways!). Training her to carpets outside has just taught her she is supposed to wee on carpets!! The fact that they are outside will not make any difference to her -- so the problem is now you have really additionally reinforced the behaviour you do not want. Yu need to take her out on a lead every time and remain with her til she goes -- not just on a single walk but every two-three hours or so.
You will also need to start by finding every place she has ever weed on the carpets and clean with enzymatic cleaner designed to destroy urine scent (a normal cleaner does NOT work). You can get a special blacklight device to spot places she has gone. Or else you will likely need to dispose of the existing carpet. Then I'd work using a crate or an xpen to housetrain and follow the motto,
100% supervision 100% of the time. No exceptions. When you do not have her at arm's reach she goes into the crate or xpen. Close off rooms she has access to and do not let her run around if you cannot reach her in a nanosecond to carry her out if she begins to have an accident. But first I would have a urine test to verify she doesn't have a UTI as this will often cause dogs to go on carpets and this will make housetraining efforts almost pointless.
I recommend buying Shirlee Kalstone's book on housetraining and also download this free book:
http://www.dogstardaily.com/after-you-get-your-puppy-0
Expect the process to take a couple of months of careful management and supervision, NO punishment, and use high-value rewards and praise (eg whatever she loves most, like a small bit of cheese or cooked dried liver given immediately after she goes, with praise). There are no shortcuts -- it will take a concerted foused effort but you will get there.
PS There's also lots of links pinned at the top of the Training section and there's info on house/crate training in the Caring For Your Cavalier part of the Library section. If you do a search on housetraining you will also find lots of previous threads with advice like this that also should help as this is a very common question.
Good luck!
