The Harmon Kardon Drive + Play connects to your current headunit via a built in wireless FM-transmitter, an optional wired FM-transmitter, or a line-out. Your Pioneer headunit should have an aux-in so the line-out option will give you the best quality.
To connect the HK Drive+Play to your Pioneer headunit, you'll need a male to male 1/8" stereo audio cable. I don't remember if the HK comes with one, but you can find them at RadioShack for a few bucks. It should look like a headphone plug on both ends. Simply connect the HK's line-out to your DEH-P9800BT's line in (on the back, if I'm correct) and voila, select the aux-in as the audio source and the sound should play through your speakers.
You'll be bypassing the Pioneer's interface for all but volume control in this configuration. If you have issues with the connection, be sure to deactivate the built-in FM transmitter in the HK's menu. Check Harmon Kardon's website for details.
--Antuan Goodwin
--Associate Editor, CNET Car Tech
I have a Pioneer DEH-P9800BT head unit that I bought and installed last Christmas and I was wondering if the Harman Kardon Drive + Play iPod interface would work in unison with the Pioneer iPod system I have in place or if I would have to remove the Pioneer and install the HK system instead. The 9800's iPod interface is terrible and I'm looking to switch and the HK is cheap so I'm hoping to find out quickly whether or not it'll work.
Thanks.

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