One problem you've got is you have a high mileage, 12 year old vehicle with lots of electronics/power "toys" - which are beginning to show signs of their age. It's one reason why I avoid older modern cars. With something pre-computer/pre-electronic/pre-emissions, it's fairly easy (and inexpensive) to keep the thing in good operating condition. But with something such as you've got, it's very often "one thing after another" at a certain point - and it becomes an exasperating (and expensive) endless money/hassle pit....