Alright, so I’m buying a 2003 R53 on Monday. It has the factory HK system, but the radio is dead. No power at the head unit. I haven’t checked anything out yet obviously, but I know I want to get rid of the HK system all together and replace with the single din touch screen available on ECS tuning, and new speakers all the way around. That being said, I’m ok with running new wire to all 4 speakers. My question is what else will I have to do in wiring everything up? Does power come in through the factory amp harness, or is it supplied to the radio itself? What else will lose functionality if anything when removing the whole HK system and what are the work around for those things? I’ve been searching all day and haven’t found a definitive answer on what all has to be done to completely remove the HK system. And get back to having a working sound system. Not really interested in fixing or using another amp at the moment, that will be for later down the road possibly. Thanks for any and all info.

 

My 2005 R53 that I picked up last month has an entire system installed. I replaced the outdated single din head unit with a single din car play unit and had my eyes on the wiring. My stereo uses the traditional harness adapter to source power, ignition signal, etc. The sound is put out through the RCA connections to a 60wx5 amp mounted under the passenger seat, that then is wired directly to the new speakers and subwoofer. It sounds fantastic and updated the car to modern day standards. You will loose the steering wheel controls unless you install and program a steering wheel control adapter.

 

I replace my complete HK system on my 04 JCW. I went with JBL Club Speakers all around (3412T Tweeter, 522F 5.25" and rear 9632 6x9s) as well as a JBL 8 channel DSP 4086 Amp. I completed the system with a Kenwood Media Player KMM-BT732HD. It all cost less than $651. These are ALL 2Ω and the Amp is similar size as the HK Amp and fits nicely in the same location. The thing I like about JBL is it is actually owned by HARMAN...same company. I added USB port to the panel that the Amp is in for future programming and ran a USB from the back of the Media Player to the glove box.
Has ALEXA and Phone capabilities as well as AUX and USB in front. Sounds amazing and NO speaker wiring had to be changed. Discovered that I had 2 bad original HK speakers as well. Was tired of taking chances on ~20yr old Amps and hoping they'd last. Original lasted 17 years, 2nd one 1.5 years and 3rd less than 6 months. I just know it now sounds amazing!