You do not have to take the car to a dealership to get it repaired. Dealerships charge more than almost any other place; but their mechanics often are not as good at solving electrical problems as an independent auto electrical specialist. Look in the yellow pages of the real phone directory (not the undersized imitations) for your region; under "automobile electrical service" or "automobile diagnostic service" or you can also look through the ads in the "automobile repairing and service" section; but ONLY consider those places that mention either diagnostic, or electrical, or fuel injection, or computer service. Places that have been in business at the same location for more than 10 years are preferable; with more points going to shops that have ASE trained mechanics. You can also search online, with an internet phone book service like www.whitepages.com. This site has detailed information about many of their business listings.
Edmunds also has listings and ratings of auto repair shops. Just click on "local services" at the right side of the dark blue bar at top of this page.