Following is very long posting how to make E46 HK amplifier work in MINI.

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Executive Summary:

Items you need : E46 HK amp, soldering iron and solder and basic screw driver and wrench tools
Process : 4 point easy soldering and rearrangement of connector pins. No wire cutting.
What you'll get : Fully working amplifier with HK stock speakers.
Vol/Bass/Treb/Balance
What you won't get : Fade and MINI HK features
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MINI's HK audio is notorious for its reliability and I'm one of the victims.
I work for major chip industry company and I still can't believe the amplifier actually a DSP "dies" so widely. There must be something wrong on their HTOL process. Anyway.

I looked up this and other MINI/BMW forums to see what would be solution to fix this amp without dropping whooping $1000 for new HK amp which I never know whether it will last.

From the posts here, FRP-3000/Sony Slimline or any after market 4ch amp seems good solution and almost pulled trigger but I don't like the following things of the solution.
1. Those amps are (quite) bigger than HK and I don't want to deal with mounting problem. Yes. I'm electrical engineer but not good at mechanical stuff.
2. Their interface is different from MINI's connector and I don't like to cut wires and loose wires that might cause short issue later. Or one day if I'm lucky to get cheap used HK amp, it would be disaster to rewire them back.
3. Since HK speakers are 2 ohm, I have to either connect them serially to make them 4 ohms or to design a crossover network. The former might toast tweeter with high power on front channel (I read one instance of it in this forum) and to design a crossover network and mounting it on the car is so nuisance. Again I 'm not good at mechanical stuff and don't like dangling stuff neither. Most importantly, how do hell I find out HK speaker's crossover frequencies?

Some of the desperate user tried E46's HK amp because they look exactly same and briefly reported that system is not working properly and only left channels are working. This intrigued me. After searching some BMW forums I found E46 HK amp's pin outs and figured out why it produced only left channels. It looked like I can make it work on MINI's system. So, I pulled trigger to buy one from eBay. After probing connections and reverse engineering of the circuits, I found followings.

1. E46 HK amp is purely analog power amplifier. It even doesn't have K-bus!
2. E46 HK amp has 10 channel speaker outputs out of 8 power amp channels.
3. E46 HK amp socket has short connection from 12V supply to any "No connection"
4. Here is the pin mappings I get from BMW's forum.

Grey ½ of connector
Pin # 13 / Tweeter Rear Right door + * Yellow Pin # 21 / Tweeter Rear Right door - *Blue / yellow
Pin # 12 / Tweeter Front Right - Blue / Brown Pin #20 / no connection
Pin # 11 / Tweeter Front Right + Blue / black Pin #19 / no connection
Pin # 10 / Switched +12v remote turn on White Pin #18 / no connection
Pin # 9 / Head unit output Front Right + Blue / red Pin #17 / Head unit output Front Right - Brown / orange
Pin # 8 / Head unit output Rear Right + Blue / black Pin #16 / Head unit output Rear Right - Brown / orange
Pin # 7 / no connection Pin #15 / no connection
Pin # 6 / no connection Pin #14 / no connection
Pin # 5 / +12v factory amp +12v supply *Red / green
Pin # 4 / Woofer Front Left +Blue / white
Pin # 3 / Woofer Front Left -Blue / brown
Pin # 2 / Woofer Rear Left +Yellow
Pin # 1 / Woofer Rear Left -Brown

Black ½ of connector
Pin # 34 / Tweeter Front Left - Yellow / brown Pin # 42 / Mid Front Right door + *Green
Pin # 33 / Tweeter Front Left + Yellow / red Pin #41 / Mid Front Right door - *Blue / green
Pin # 32 / Tweeter Rear left door - * Yellow / brown Pin #40 / Mid Front left door + *White
Pin # 31 / Tweeter Rear Left door + * Yellow / black Pin #39 / Mid Front left door - *Blue / white
Pin # 30 / Head output Front left - Brown / orange Pin #38 / Head output Front Left + Yellow / red
Pin # 29 / Head output Rear Left - Brown / orange Pin #37 / Head output Rear Left + Yellow / black
Pin # 28 / no connection Pin #36 / no connection
Pin # 27 / no connection Pin #35 / no connection
Pin # 26 / DC ground factory ampBrown
Pin # 25 / Woofer Rear Right +Blue
Pin # 24 / Woofer Rear Right -Brown
Pin # 23 / Woofer Front Right +Blue / Red
Pin # 22 / Woofer Front Right -Blue / Brown

Here is the helping factor of MINI's HK amp.
1. If MINI's HU doesn't detect HK amp, it will turn into normal HU that controls vol/bass/treb/balance/fade using analog way and send it to connector
2. But it doesn't have rear channel input connection.
3. Here is pin mapping table from GBMINI's site.
http://gbmini.net/downloads/PGEN/hk-plug-grey.htm

Grey 1/2 of HK Plug

Pin # 13 / Tweeter Front Right + Blue / Black Pin # 21 / Tweeter Front Right - Blue / Brown
Pin # 12 / Tweeter Front Left - Yellow / Brown Pin #20 / no connection
Pin # 11 / Tweeter Front Left + Yellow / black Pin #19 / no connection
Pin # 10 / Remote turn on White Pin #18 / no connection
Pin # 9 / Head unit output Front Right + Brown / Black Pin #17 / Head unit output Front Right – Blue / Brown
Pin # 8 / no connection Pin #16 / no connection
Pin # 7 / no connection Pin #15 / no connection
Pin # 6 / no connection Pin #14 / no connection
Pin # 5 / +12v supply Red / Brown +
Pin # 4 / Woofer A Rear Left + Blue / Red
Pin # 3 / Woofer A Rear Left - Blue / Brown
Pin # 2 / Woofer A Rear Right + Blue
Pin # 1 / Woofer A Rear Right - Brown

http://gbmini.net/downloads/PGEN/hk-plug-black.htm
Black 1/2 HK Connector

Pin # 34 / Door Front Left – Yellow / Blue Pin # 42 / no connection
Pin # 33 / Door Front Left + Yellow / Grey Pin # 41 / no connection
Pin # 32 / Door Front Right - Brown / Red Pin #40 / no connection
Pin # 31 / Door Front Right + Yellow / Red Pin #39 / no connection
Pin # 30 / Head output Front Left - Yellow / Brown Pin #38 / Head output Front Left + Yellow / red
Pin # 29 / no connection Pin #37 / no connection
Pin # 28 / no connection Pin #36 / no connection
Pin # 27 / KBUS White/red/yellow Pin #35 / no connection
Pin # 26 / GROUND Brown -
Pin # 25 / Woofer B Rear Right + Brown / Red
Pin # 24 / Woofer B Rear Right - Yellow / Red
Pin # 23 / Woofer B Rear Left + Yellow / Blue
Pin # 22 / Woofer B Rear Left - Yellow / Grey

Anybody who is interested in following my steps, I recommend to print out GBMINI's mapping table and write E46's mapping on the same pin number. It would help you when you do the mod on MINI's connector.

The reason I explain all these clutters instead of just explaining what to do is that there are two way to do it.
1. Revive HU's rear connection to both of HU's and HK's connectors and make use of it. According to the one user in this forum, HU indeed has rear outputs but simply connector doesn't have connection pin there. If we connect them, we can bring rear channel to HK amp.
2. Connect front channel output to rear channel output in HK amplifier defeating "fade" function of HU.

I have chosen #2 way because of the following reason.
1. Again, I'm not good at mechanical thing and don't want to open front side of MINI's interior additionally. Tearing off the rear interior was already big enough endeavor for me.
2. Rear speaker of MINI is actually dual coil woofer. So ideally woofer A and woofer B should have identical input to have best performance according to JL Audio's homepage I googled. I decided to making it happen by connecting front channel input to rear channel input and connect both of front and rear woofer outputs to woofer A and B respectively.
3. Once I connect front and rear channel input, there is no more front/rear difference on HK amp output. So I would have less connection mismatch on connector side. This will help reducing rearrange of connector pins later.

If there is somebody who knows speaker system, I'd like to hear the option 1 as well. Unlike the conception of people, electrical engineer knows only small field of he's working on. So I'm not much better than any other people who doesn't major electronics for speaker systems, which is another reason I didn't want to design crossover network.

First of all, you have to buy E46's HK amp. I got it from eBay at $70 but it usually goes around $100. I saw one in local craiglists as well.

Once we connect E46's HK amp to MINI, it will have these problems in summary.
1. It drives only left channel sound
2. It screws up whole K-bus and disables steering handle button (not steering wheel itself! ), Nav buttons, signal lamps indicator on dash board (not signal lamp itself) and so on ...
3. It has only front channel input from HU

Let's resolve these issues one by one.

#3. As I wrote above, I simply connected front input to rear input. To do this, we need to open the amp and pull out connector board. I'll put a picture later if needed but it's really simple process. Just remove screws and pull out the connector board. It will come off easily. On the bottom side of board, connect followings. They're next to each other. So just add solder and connect two pins. Look up the pin mapping table to make sure you're connecting correct one.

a. Pin 8 -- Pin 9 : HU Front Right - HU Rear Right (+)
b. Pin 17 -- Pin 16 : HU Front Right - HU Rear Right (-)
c. Pin 29 -- Pin 30 : HU Front Left - HU Rear Left (-)
d. Pin 37 -- Pin 38 : HU Front Left + HU Rear Left (+)

Re-assemble it. You're done soldering part. By just doing this, you already have full 6 speaker working! Left/Right channels are mixed up though. For some people this with solution for #2 would be sufficient. You just don't have control over R/L balance and stereo effect will be reduced. But what the heck. At least you have sound on your car at the cost of $100!

#2 is caused by the fact that E46 HK amp shorts 12V to any No Connection (NC) in its socket as I wrote on my findings. So none of K-bus slave is able to drive the bus. By simply disconnect it from connector, we can solve #2. It's ok to leave it unconnected. K-bus has pull-up resistor on master side. So left it open is the way it's supposed to be.

To do this, we have to disassemble the connector harness. If you look at the connector harness closely, you'll find that there are two small clips that hold gray and black connectors inside. Pry the clips and pull the connectors. They'll come out easily.
Find K-bus from black connector. It's pin 27 next to big GND pin.
Press the metal pin of connector with small Philips driver or something and pull out the pin. It will come out easily. If you're not interested in solving R/L balance issue. You're done. Reassemble the connectors into harness and using black electrical tape, hold K-bus pin you pulled out around wires tightly. You don't want this pin loose around. If you want to have correct R/L speaker outputs, don't reassemble and go to next part.

#1 is caused by different speaker mappings between MINI and E46.
Before we start, let me explain a bit of E46's speaker mapping as there could be multiple way to finish this section.
E46 HK amp is essentially 8 channel power amplifier but has "10" channel output on connector. How do they to that? They simply drive front mid range speaker AND front tweeter with same amplifier.
From the pin mapping table, followings are connected together.
Pin 42 (MFR+) == Pin 11 (TFR+)
Pin 41 (MFR-) == Pin 12 (TFR-)
Pin 40 (MFL+) == Pin 33 (TFL+)
Pin 39 (MFL-) == Pin 34 (TFL-)

Since I decided to use both Front(F)/Rear(R) woofer output to Woofer A/B respectively, I swapped pin 22 and 23 with pin 1 and 2.
Pin 1 and 2 <--> Pin 22 and 23

As MINI's door speaker is full-range speaker, I decided to exploit that the fact above that one amp has Mid and Tweeter signal. So, I moved
Pin 33 and 34 (DFL) --> Pin 39 and 40 (MFL)
Pin 31 and 32 (DFR) --> Pin 41 and 42 (MFR)

Now, for tweeter, it's straight forward as there are only two unused power amp outputs.
Pin 11 and 12 (TFL) --> Pin 31 and 32 (TRL)
Because my F == R, it's fine.

Now assemble the connector and plug into the amp. You're good to go!

Tip.
Before you pull out any pin from connector, use some labeling tape to mark original pin with its function and +/- sign. It will help to put it back when you have real HK amp as well as rearranging.

After this modification, I can hear that the T/M/B balance is different from old HK audio and Bass/Treble control doesn't help much. Mid-range seems a bit weak. It could be just my perception so somebody may be ok. This speaker re-arrangement could be done differently with different sound outcome.
If you have better idea, let me know.

I'd better go. Post any question on this mod. I'll try answer as much as I know.
Motor on!
Jinux

 

I'm going to try this. There are several versions of E46 HK amp. Are they all the same w/respect to pinout, functionality? Maybe the differences are in the mount?

 

I bet they have same pin outs on connector side. If you have tester to test short circuit, you can find correct connection from PA to connector but eBay seller says my amp is compatible to 99~ 03(?) or so BMW 3 series and it was made in 1999. And I haven't seen any different pin mapping on internet.

Good luck.

 

You've done a very cool thing figuring this out. It occurs to me that using a rewired E46 amp might be the simplest way to replace the Harmon Kardon HU with an aftermarket unit. Even when I get the E46 amp in and working I still won't have the ability to play mp3, read files from a USB flash drive, etc.

The rewired E46 amp:

• drives the stock 2 ohm speakers,
• is the same size and fits the same physical location as stock,
• uses the same connector,
• has eight output channels
• has four balanced inputs, so rear L/R audio signals could be added.

I wouldn't mind finding a connector for the E46 amp. It would be nice to have some sensitivity, frequency response data on the various outputs.

 

I see what you're going to to and that's what I thought too - replacing HU with after market one.
There is one problem though. E46's HK amplifier output to MINI speaker doesn't have flat frequency response.
Mid low range is weak and Treb is too strong.
I have to knock down Treb and boost Bass but it's still not balanced well.
HU with equalizer may be able to compensate this unbalance.

 

One thing I am curious about - whether the HK needs balanced inputs. From the pinouts you would think so but perhaps the neg side of the input is grounded internally anyway. If balanced inputs are needed it could be a problem. AFAIK the preamp output on aftermarket HUs are single-ended.

 

got my e46 amp & i will be trying this method. sounds kool

 

The E46 HK amp has differential input (balanced input) and I guess this full differential structure is kept through PA.
I didn't reverse engineered the board schematic but there are OP amps that I guess for filtering and cross-over. So if the first stage is fully differential, you can tie one of the input to GND and apply single ended input to the other input. It depends on the first stage amp architecture though.

This way you can send two single ended output to HK amp and they may be used as front and rear signal.

Good luck!

-Jinux

 

Mine came in today. This is a good project.

 

Navigation screen freeze's when the amp is hooked up! Don't mind the blinker or steering wheels controls. Anybody figure out what or if there is a wire I can pull from the amp connector to stop this from happening.

Gonna try two of the wires that lead too the nav audio wires

 

Did you do the pin swapping in the connector described earlier in the thread? This is not a plug-and-play. :ducking:

 

You have to disconnect K-bus line from the connector.
On my original posting, it is written as

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To do this, we have to disassemble the connector harness. If you look at the connector harness closely, you'll find that there are two small clips that hold gray and black connectors inside. Pry the clips and pull the connectors. They'll come out easily.
Find K-bus from black connector. It's pin 27 next to big GND pin.
Press the metal pin of connector with small Philips driver or something and pull out the pin. It will come out easily. If you're not interested in solving R/L balance issue. You're done. Reassemble the connectors into harness and using black electrical tape, hold K-bus pin you pulled out around wires tightly. You don't want this pin loose around.
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Once you disconnect K-bus from connector, it won't disturb any original equipment's operation.

 

Ohh I Was Lazy. there"s no fix for the flasher right??? sending paypal/baby gift now!

 

Once you disconnect K-bus from the connector, your flasher (and ALL normal functions) will be back to normal operation. Simply MINI control system doesn't know whether there is amp or not, except speakers because they're now driven by power amp.

ps. Thank you very much for the donation. I refunded excess amount from what I was expecting and greatly appreciated.

 

Just got done hooking everything up and it works fine now
It's just a matter of tapping into the right speaker wires.

That was for everyone who was late with donations. Lol
You should have kept it.

once you get your amp all you have to do is tap the rightside speaker wire to the leftside. And dis-connect the k-bus wire.(thats the key)
Here is another link with basic wire write up.
http://www.gbmini.net/downloads/HKconnections.pdf

 

I've checking a some wiring diagrams on bmw-planet for the E46 HK. The unused connections look to be audio output and control to a subwoofer amplifier:

Speedometer output - changes Sub volume with vehicle speed?

I don't know yet whether the LPF is in the HK amp or not. Frequency response measurements of each channel to follow.

 

I made a fixture and took some data on the E46 HK amp. The two types of channels provided by the E46 HK amp (front and rear) have different crossover points:

These are relative gain values with a fixed input level:

Rear

• Low frequency output - approximately flat, 0dB gain.
• High frequency output - high pass @~2.9 kHz, +6dB gain @ 10kHz.

Front

• Low frequency output - low pass @~400 Hz, +8dB gain @100 Hz.
• High frequency output - high pass @~400 Hz, 0dB gain @10 kHz.

This is a generalization. There is some cross talk among some channels and relative peaks and dips occur in the pass bands.

 

Bradly99,

This is very good data. Now I can see why there is excessive treble ( my tweeter is connected to rear HF output which has 6dB gain) and weak bass (mismatched and unbalanced front/rear LF output ).
I don't have good idea come up how to resolve this though.

 

I have partially traced the schematic of the E46 HK and have run some spice simulations on the unmodified equalizers and crossovers. This amp was tailored for a particular car. I am going to modify it to give a better response for the Mini.

After tracing the schematic it doesn't appear to be difficult to do. The question is what mod's to make. Most of the modification is clipping capacitors out of the amp to remove the custom EQ.

• Left Rear - dual channel full range
• Right Rea - dual channel full range
• Left Front - two channels, one full range, one HPF @1.5 kHz (?)
• Right Front - two channels, one full range, one HPF @1.5 kHz (?)

 

I finished the first pass at the amp mod's. Now I have to do the connector and try it out to make adjustments (14 wires to be moved).

This mod keeps the E46's F/R and L/R channel assignments. Front and rear are connected on the PCB at the connector. I might be able to run a fade control to the rear panel on the amp. I went for basically full range rears with a HPF @30 Hz, 50 Hz to 10 kHz for the front woofers, front tweeters HPF @2 kHz.

Some measured data:

 

I installed the modified E46 H/K. It's clear and loud, plenty of bass and treble adjustment. I'm still not that happy with it though.

 

Thanks for the info guys! @Bradley99, any tips/info on how you got the EQ settings and other EQ errors corrected? About to start the E46 > Mini amp conversion too.

 

Thanks for the info guys! Bradley99, any tips/info on how you got the E46 amp to have a decent EQ response? You mentioned cutting out capacitors and moving 14 more wires. Would love to know what you did. About to start an E46 > Mini mod too.
Thanks!!!

 

Just finished the E46-to-Mini amp conversion. Works great! I do have a little higher midrange than the original E50 amp, but still sounds decent. I was able to increase the bass response a bit by switching the woofer pins so the lower frequency signal gets to the low woofers in the Mini. Here are the woofer the pins I switched using Merongi's pinout map:

Wire at pin#1 - moved to Connector pin#24
Wire at pin#2 - moved to Connector pin#25
Wire at pin#3 - moved to Connector pin#1
Wire at pin#4 - moved to Connector pin#2
Wire at pin#25 - moved to Connector pin#23
Wire at pin#24 - moved to Connector pin#22
Wire at pin#23 - moved to Connector pin#4
Wire at pin#22 - moved to Connector pin#3

 

Sorry to resurrect this thread. I'm wondering if someone can point me to which two sets of pins need to be soldered together for this mod? Having a hard time following the written guide for the soldering portion. I know it's the set of pins on the bottom of this picture, just not sure which 4. Thank you.