CD43 Business CD Head Unit Installation....

[George M]

Gents,
I am pleased to report subject radio has been successfully installed. It wasn't easy but few things worth having ever are.
Hope you enjoy the following write up:


Fortunately the PO of the head unit had the original booklet and code
card unmolested.


Unraveling the wiring DNA code on the kitchen table. First effort to wire the radio was unsuccessful. This is what happened....


The primary reason for this post is to help others with this conversion. The two people I talked to that performed the conversion really didn’t know how the radio was wired…both purchased an aftermarket plug with pre-assigned wires to splice to the car harness. I personally don't like to rely on aftermarket plugs which can many times be wrong or have an errant wire in the wrong place. I got to know where all the wires go. I didn’t want to go the aftermarke plug route and it almost cost me. I wanted a factory BMW plug and Rigmaster sent me one from his parted ’92 525i for a nominal cost…Thanks Bret. Here is the issue....I put together a wiring diagram above constructed from the radio booklet with a pic of the pin config. from Bentley for ’91 and later BMW’s. Winfred…I solved the reason why these plugs are not interchangeable to all year BMW’s after 1991. BMW didn’t change the pin configuration on the excellent sliding clasp common radio connector that didn’t change over the years but did change the damn convention of which pins pertain to what no. callout for each wire address. The picture shows conventionally marked nos. in black from Bentley for ’91 and later radios. The colored nos. represent the correct pin callout convention for the later CD43 business CD head unit offered on late model BMW’s. Go figure. I presume they did this to mitigate EMI but it sure caused a whole lot of confusion and anxiety for me…well at least as excited as I get these days. The first time I hooked up the radio, I attached it to the ’91 Bentley plug callout config. turned the radio on and nothing. I am grateful to a higher power that I didn’t fry the radio as many wires were attached to incorrect destinations.
Next I removed the connector and checked the fuse…perfect so dodged a bullet there. My mind was reeling of course thinking that UPS abused the package in transit in spite of the radio being meticulously wrapped….Many Thanks Oscar…the radio was in perfect condition and I mean perfect. Next I didn’t know what to do so removed the connector and started fishing around only to find that the radio pin addresses were etched into the back radio plug adjacent to the pins. A quick comparison with Bentley and there is was. I was both relieved, agitated that BMW would change the pin destinations without changing the plug over time…and concerned that I fried my new radio at the same time. There was hope...but did I fry the radio by mis-wiring it? Had to wait until I pulled the car harness all apart again and resolder it correctly to the colored numbers above to find out. Note that pin nos. 1-6 are the same for all years. It seems ludicrous that BMW would throw this curve ball for the same design plug but they did. Other thing that no one would answer is could I isolate all the negative channel outputs from this factory radio and wire it successfully like I had my last Kenwood head unit and as the original factory radio is wired. The answer is yes which begs the question as to why BMW goes the trouble and added cost of running separate (-) channel outputs to the post amp after model year 1990 but they do…presume it is for incremental sound improvement versus sharing a common earth...but imperceptible to my ear. That is precisely how you wire this radio to pre-1991 BMW’s…connect only the (+) leads for the four channels respectively to the car harness/amp and do not connect the (-) channel outputs from the radio at all. Isolate the (-) leads independently with electrical tape and do not ground them. Do run a separate ground wire from the radio chassis to the car’s body however. Other thing you will need is a VW-20 antenna adapter to connect the conventional power rear window antenna co-ax from the car to this radio…Thanks Mike Holbrook for the tip.


Straight on shot of radio…couldn’t be more pleased with the way it looks. The radio unlike any other radio I have seen in these cars looks like it belongs. Here is the kicker…it even sounds better than it looks. I am astounded by the sound. I never liked the factory head unit…thought it was a weak radio and it is. I upgraded to a Blaupunkt Toronto and it was better but there were many quirky un-BMW like qualities to that radio…I hated the credit card feature…thought it was gimmicky and believed it had a cheap amp and wasn’t impressed with the sound quality and so upgraded to a Kenwood 715S which sounded terrific. This radio however blows it out of the water. I had no idea the sound would be this good running through the factory amp and stock 10 speakers…couldn’t be more pleased. Heard more depth to some of the CD’s I tried that I hadn’t picked up in other systems…a very impressive stock head unit.


Side shot of the radio. In summary, I highly recommend this upgrade to anyone considering an aftermarket head unit. You should be able to pick one up for around $300 or so or comparable to a replacement head unit. Your challenge will be to find a real nice one…I got lucky. Someone with a late model E-36 or Z3 that has to have an audiophile system will occasionally put a CD43 up for sale. I put a query on the Z3 board and got a response. Personally, I would never sell an original BMW factory radio out of a clean BMW but some do for the money. If I were ever to upgrade, I would always keep the original radio to sell with the car. A final note is…the tactile quality of the buttons, ergonomics and overall sturdiness this radio exudes is second to none. Also, the display is a perfect match for the rest of the lighting.


Of course I had to throw in a pic of my car…what the radio is attached to.

My post in thanks for all the great people on this forum that have the same passion for these cars.
George
90 735iL/149k
P.S...will keep these pics up for a while on my webspace. If you are interested, save the pics into your hard drive before they are taken down.

[Martin in Bellevue]

Looks great George! That is, the radio & that sled.

[George M]

Thank you Brother....appreciate your comment Martin.
George

[Brandon J]

Wow, that looks awesome. Thanks for the input. Did you do any research to see if a BMW 6 disc cd changer could be used also? Does the illumintation dim with the rest of the dash lights?

hmmm...that would be nice to see and hear in person.....ahem e34 meet
btw, the car looks very clean

[winfred]

i was wondering how it would sound, i know the 96 and up e36 tape decks really suck for sound quality, even with the harmon amp/speakers (guess you can't polish a turd, meaning the head unit) and the grand master of shitty sound systems the e39, that thing reeks, plus it's a odd size and part of the obc, id walk away from a car that sounds like that at the showroom. i know the amp and speakers are pretty decent and on 95 and older cars the pioneer head unit blows the alpine away for sound imho

[Jeff N.]

swwweeet. I want one!

[Scott C]

Does the radio channel show on the instrument cluster as well? (Maybe only 95?)
Thanks,
Scott

[Jr ///M5]

Nice work George. That unit really does look like it came with the car, it looks right at home and updates the look of your console area. Good idea, glad you shared your hard work and research with us. Wouldn't expect anything else from you, but a top notch install procedure.
Yessir, a high class unit for a high class car. You really have a lovely car, and the color......=) one of my favorites!
Now with the new tunes in place, you're just about ready for a road trip, right? Say, around August 8th, Chicago area??? =)

Great job George! It took the patience of Job to figure out the wiring, and to document it so it can be shared by others is to be commended.

Lovely car...

[MicahO]

Looks great - right at home, and CD audio is now right at your fingertips. It's also great to hear that it looks as good as it sounds.

With a new BMW Harmon Kardon system in the driveway, I know what Winfred is talking about. It doesn't sound all that bad (and I prefer the exhaust and engine note anyhow). But compared to the Bose/Nissan Surround Sound system in Jen's car.....

Good factory fidelity - nothing better! Enjoy it!

[George M]

Glad you guys like it. As with everything, it is a balance. With radios...the balance is aesthetics, fidelity and cost. Everybody has a different priority...with me, the afore mentioned are of equal weight. For some..nth degree sound quality rules and how the head unit looks doesn't factor in as much and are willing to pay $2K to install a killer system and tear out the old speakers and factory amp. Many people on this forum have that kind of system that will blow mine away in sound quality. With me I was looking for a balance of all these things trying to preserve the originality of the car a bit and yet still upgrade sound peformance at a reasonable price.
Brandon....I didn't research the 6 disc changer compatibility as I currently don't have one in my E-32...one of the only options my car didn't come with.
If I installed one, I would opt for a late model changer mostly for performance and reliability and run the factory co-ax from the CD43 back to the trunk. It is possible the original changer would work in these car but I don't have an answer for you. I know the plug itself is different on pre-91 cars but possibly compatible on '91 and later E-34's when the went to the later radio connector with integral changer co-ax. As to the illumination...it matchs perfectly with lights off in daylight or on in a dark garage...checked it both ways. The separate illumination wire compensates for light, reducing the illumination of the display and providing peripherial lighting to the knob etc when the lights are turned on. Scott...I honestly don't know if the center display will show radio function...a very good question. I used that feature so infrequently when I had my original radio in the car that it didn't occur to me to even try it. Will have to give it a go :-)
Jr...many thanks for your comments. It is your car I covet of all the cars on this forum. I hang out here with "my sled" because of the people mostly.
I do love my car but your M5 because of its rarity, condition and performance is really something to behold...and as you say the color ain't bad either.
And Micah...glad you are still hanging out as with many who have moved out of the E-34 fold as the true car guy you are. As you know time marchs on and factory systems continue to improve so my modest system won't hold a candle to many of the high end late model cars out there not to mention some of the very trick aftermarket installations...but for what it is...sounds pretty darn good...especially at fun song with the windows down and roof open on a perfect sunny day on the expressway with the peddle down :-)
Cheers to my homies out there.
George