I just recently installed an Alpine IDA-X100 in dash deck.

I was warned that by doing so and not adding a special wiring harness I would lose my chymes from the doors being open, key in ignigtion, etc.

Also, Apparently the airbags could be affected.

I don't belive "wiring harness" is the correct term, but for lack of a better one this harness cost $149.99 from bestbuy.

They are available all over.

Theres more to be read elsewhere, just my 1.5cents.