By default, the Kenwood KCA-R6A remotes (very common, available many places) also work

This remote available from Crutchfield works very well right out of the box, and does not require any reprogramming or kernal hacks. It does not have 100% of the functions of the RioCar remote, but the only one missing that I find important is the key to scroll through the info modes.

tanstaafl.
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