Response to "What radios/CD's can be put in the M-Class?"

Submitted by	Category	Response to	Chassis W163	Public
Ken K. Yee on 07/19/2000 at 01:31 AM	Frequently Asked Questions	What radios/CD's can be put in the M-Class?

Omar's Bose Replacement

From osultan@cisco.com:

Since a few of you have asked, this is what I found out about the Bose system in my 99ML430.

First, the six-speaker stuff is seriously misleading. It is really four speakers. The front speakers are 2-way coaxial speakers: a 6.5" woofer and a tweeter mounted together and wired in parallel, with a simple bipolar capacitor as a high-pass filter for the tweeter--strictly low-tech. The rear speakers are one-way 5.25" speakers. The "sub-woofer" under the driver's seat is a 6-8" driver in Bose's usual transmission line enclosure. I could not tell if the amp for the sub is in the black box, or located somewhere else. The impedance on the door speakers, both front and rear, is 2 ohms, which is lower than most speakers, but higher than their usual 0.5 ohms.

Electrically, this is different than Bose systems that I have in the past: the speakers are not amplified, they are driven by the head-end like a normal system. All connections are friction-type and clip-type so their is no soldering needed. This means that upgrading the speakers alone is relatively simple--with a few caveats noted later on--but upgrading the head-end alone is a tougher proposition, since few amps can drive a 2 ohm load.

Based on the cost of the base system and the upgrade in the ML, I am disappointed by the quality of the components I have encountered so far. The speakers are strictly middle of the road quality and engineering--the drivers are paper cones and they do not even appear to be coated. The tweeters are pretty generic looking and the rear speakers are only one-way.

As I said, once my radio extraction doohickey shows up, I will take a look at the head-end and will report back on what I find.

So, I chose to upgrade to MB Quart PSC 216s--a component style speaker setup. I am very happy with the results. The main concern is the sound end up bright--a result of the tweeters being mounted up higher and (I am guessing) the equalization curve built into the Bose amps. One of the reasons I chose the MB Quarts is that the xover allows me to attenuate the treble up to -6.0 dB. If you choose to upgrade with another 2-way, you can get the same effect, more or less, by using the treble tone control.

Installation wise, it was pretty straight forward:

1. I popped of the door panel--a process discussed other places on this list.
2. I chose to put the tweeters in the sail panel by the A-pillar, using the angled flush mount, so they tweeters point towards the passengers. This was probably the hardest part, since I had to cut into the sail panel. There is only a small area to place the tweeter, since the hole has to clear the dash when the door is closed and the mounting clip on the back of the sail panel. You can also surface mount if you are squeamish about cutting. MB Quart provide a stick-on template, which greatly facilitates things. In an inspired move, the day before I planned to put the speakers in, I popped off the sail panel, took it into Home Depot, and had them mix me up some custom tinted semi-gloss enamel that perfectly matches my Sand interior. I put the paint into a sprayer and painted the grille and housing before assembly/installation.
3. The woofers drop directly into the existing housing, so they took all of about 30 seconds to install.
4. I wired everything to the xover and attached it with velcro to door panel in the area behind the cutout for the woofer (i.e. if you pop out the woofer, you will see the xover). If you go the xover route, look for one that is really small, or is flat/skinny, since there is not much space back in the door with the speaker housing, structural steel beam, and window lift mechanism.
5. Re-assembled everything and voila!

So, for me, the effort is worth it. I have a lot more of the acoustic qualities I am looking for. The tonal balance is not quite right--I ended up using the xover to attenuate the tweeter by -3dB to cut down on the brightness, but it is not worth messing with further until I figure out what I am going to do with the electronics.

OK, so my two year old went off to bed and I got bored and noticed that the slots for removing the head unit were about the same width as the brass collar stays I use in my dress shirts, so. I an intuitive leap...and...lo and behold, the collar stays worked--be on the lookout for car stereo thieves in dress shirts ;-)

So anyway, I can happily say that the Bose "up"grade is consistent--it seems component quality is mediocre throughout: the receiver was made by out friends at Matsushita, which I guess should not have been a surprise, since the CD-changer is a Panasonic unit. The reference number stamped printed on the label below the MB part number is CQ-CP2810Z, which is remarkably similar to CQ-CP28xx, Panasonic's last generation line of receivers. Anyway, mated of the receiver housing is a secondary housing which houses what looks like amp and/or equalization circuitry, which I will assume is Bose's value-add to this whole set-up--or not, since I am not familiar enough with Panasonic's product line to know what their generic receiver looks like.

Anyway, the outputs on this puppy are all speaker level. "So, what does that mean, Omar?" you say....well I am glad you asked.

[Editorial note: its getting late and I am getting punchy, if you haven't already noticed]

Well, in general, it simplifies most upgrade scenarios:

If you want to keep the receiver and simply add a better/more amps and upgrade speakers, this is very doable, you will simply need to buy a line output converter (LOC) available at Crutchfield and most car audio places worth their salt (about $30).

If you want to toss all the electronics, all you have to do is toss the receiver, there are no other electronics to find/bypass in the bowels of the car. Note, if you follow this route, you are also committing to upgrading the speakers, since most after-market head-ends are not 2 ohm stable and cannot drive the Bose speakers (see previous post).

You can even leave the head-end alone and upgrade just the speakers. Assuming you address the tonal balance issues (i.e. use the tone controls, a resistor pad or an xover), the only thing you will lose is some volume, since the amp is driving higher loads than it was designed for. If you consistently listen at high volume levels with this set-up, it may shorten the life of the head-end (which may not be a bad thing).

BTW, I was surprised at the amount of space that is available to work with behind the dash, so find space for an amp should not be a problem.

The only open issue is what to do with the infamous black box under the driver's seat. Once I figure out exactly what is in the box (i.e. just a driver or an amp too), I will share.

When I am a little more awake, I'll pull out my trusty multi-meter and create a pin-out of the connectors on the back and post those too.

Well, for better or for worse, Bose's contribution to the MB Upgrade goes beyond the silk-screening on the cassette compartment door!

The speakers in the back doors are 2-ohm, 1-way 5.25 inch drivers that Bose actually makes. I wonder if you get any back speakers without the upgrade: It seems strange that Bose would provide speakers for the back doors but leave the generic 2-way in the front doors. Maybe because Bose only makes drivers, no two-way or three-way speakers.

The famous black box under the drives seat is also a dual-voicecoil Bose driver in one of their patented transmission line enclosures--this one actually looked like pretty good build quality.

Now the fun part: the electronics. So, in an earlier post I said I wasn't sure if there was any other electronics in the upgrade. Well, after stuffing several thousand dollars of Alpine and MB Quart gear into my ML, and realizing that is still sounded pretty much the same, I figured there was more to the Bose "upgrade" DOH!!!

So, after much foraging, under the dash, on the driver's side, way up in the corner (follow a line from the cup holder straight back towards the firewall) is a Bose combo line-output-converter/amp/equalizer. So this little puppy takes the speaker level output form the head-end, applies an equalization curve to it, and then pumps this out to the four speakers plus the "sub-woofer". The main implication of this is no matter what head-end you use, it will not sound much if any different.

So, I pulled this guy out and re-connected the speaker harnesses and the world is a much better place.

So, all this is really just a prelude the bigger project:
- Install the Alpine CAV-1005 with the DVD Nav and 6 disc changer
- Install the Nokia CARK-91H hands-free kit an utilize the built-in mic in the headliner
- Have both Aline Nav and Nokia use the integrated cell/GPS antenna for the MY 00 ML

So far, I have most of this roughed-in and working. As soon as it is done, I will post details.

BTW, here are some pin-outs that I have amassed along the way:
MB Head-end Plug A (Power and controls): -- -------- ---- - --------------------
PIN COLOR FUNCTION 1 Blue Speed dependent volume control (not implemented) 2 Brown Not used--goes to Ground 3 Grey Phone Mute--ground to activate 4 Red Constant 12V 5 Orange 12V Antenna Trigger (I think this is actually used as the remote trigger for the Bose unit) 6 White Illumination 7 Pink Ignition 8 Brown Ground

MB Head-end Plug B (Speaker level outs): -- -------- ---- - --------------------
PIN COLOR FUNCTION 1 Red Right Rear + 2 Grey Right Rear - 3 Tan Right Front + 4 White Right Front - 5 Blue Left Front + 6 Green Left Front - 7 Pink Left Rear + 8 Orange Left Rear -
MB Head-end Plug C (CD Changer controls): (didn't document)
Bose Unit Plug A ---- ---- ---- -
PIN COLOR FUNCTION 1 Blue LF + Out 2 Green LF - Out 3 Grey RR - Out 4 Red RR + Out 5 Tan RF + Out 6 White RF - Out 7-11 Open 12 Orange LR - Out 13 Green LF - In 14 Orange LR - In 15 Grey RF + In 16 White RF - In 17 Red RR + In 18 Pink LR + In 19 Tan RF + In 20 Blue LF + In 21-24 Open
Bose Unit Plug B ---- ---- ---- -
PIN COLOR FUNCTION 1 Grey Sub Out 2 White Sub Out 3 Pink LR + Out 4 Red 12V Constant 5 Blue Sub Out 6 Tan Sub Out 7 Orange Antenna Trigger (remote turn-on?) 8 Brown Ground
The other project has been equally fun and frustrating--and I am impressed as to exactly how much of a Mercedes ML you can take apart with a cheap mini slotted screwdriver and an old putty knife! Stay tuned for more details.

This is how you remove the center console:

1. Take all the stuff our out the console bin

2. There are two small black Phillips screws in the bottom--remove those

3. You will now have access to the two black mounting screws for the console cover--remove these and the console cover

4. If you look straight down into the hole, you will two more metal screws--remove those

5. There are two locking electrical connectors that feed the power window switches in the back of the console--disconnect those. I found the second one (the bigger one) really hard to access and found it easier to pop out the fascia that the switches are housed in to get at the second connector (fat fingers). The fascia is held in place with simple snaps.

6. Remove the wood panel with all the switches etc in it. I don't have the official German precision engineered panel removal tool, to I use a 1.5" putty knife--seems to work great. Place the putty knife blade between the edge of the panel and the plastic of the console housing on the front corner (either driver or passenger side). It is important to pry the panel up from the side--not from the front or back:
Pry Here
_____________________________VV
| |
| 1 2 3 4 D N R P |
| [ 0] |
|_______________________________|
Gently pry-up and you will hear a pop as the snap releases. There are about 4 or 6 snaps symmetrically placed on the sides.

7. Once the panel is loose, pivot it forward at a 45 degree angle and disconnect the electrical connectors underneath--there are about 6-7 and they are all unique so you do not need to document where each one goes.

8. Put the key in the ignition and move it to position 1--make sure the emergency brake is engaged, put your foot on the foot brake and shift the car into neutral, then turn the ignition back off. You need to do this to get the shift lever out of the way.

9. Remove the wood panel

10. There are two metal screws behind the gear shift--remove those

11. The console housing is now free--you remove it by picking it up and moving it back at the same time.

12. Remove the insulation

13. At the back of the black plastic air duct (by the rear seats), you will find two black screws--remove these

14. Remove the duct by picking it up and moving it back at the same time.

15. Stop and have a swig of beer.

Towards the back of the console innards, you will see an grooved aluminum housing--this is the transfer case module (part number R163 545 01 3). You can either connect to the module with an insertion harness available from MB or by tapping into the wires that connect into the transfer case module. I opted for the insertion harness. The part number for the CAN Bus adaptor and bracket is Q6 54 0011. The harness I got is part number Q 6 54 0010. This is actually the harness that comes as part of the GPS installation kit, so it had a bunch of extraneous stuff on it that I did not need/use, so there may be a cheaper harness out there that doesn't have all the extras on it.

Connector wise (look at the CAN Bus adaptor with the two small connectors the left):
CONNECTOR 1 (on the left)
[A B]
PIN A connect to green wire from insertion harness/transfer case module B connect to white wire from insertion harness/transfer case module
CONNECTOR 2 (in the middle)
[C D]
PIN C unused D unused
CONNECTOR 3/Transfer case wiring
[ 9 8 7 6 5 4 3 2 1] [18 17 16 15 14 13 12 11 10]
PIN 1 Ground 2 No connection 3 Vehicle Speed Sense (green on harness) 4 No connection 5 No connection 6 Reverse Output (white on harness) 7 No connection 8 No connection 9 Ignition 10 No connection 11 No connection 12 12V 13-10 No connection
I have taken the console apart about 6 times in the process of removing the Bose and installing/troubleshooting the Alpine. Now it takes about 5 min. The first time, when I was exploring--it took about 90 min and a lot of trepidation!

So, when I last left you, I had wrestled the Bose system out of my 99ML430 and was about to install the following:

-Nokia CARK-91H Handsfree cradle for my Nokia 6160 phone
-Alpine CVA 1005
-Alpine NVE 8551 Navigation
-various MB Quart speakers, JL Audio subs and supporting electronics and wiring

I will report on the Nokia cradle install first.

I had two design criteria:
- low-profile install
- integration into sound system.

To support the low-profile install part, I wanted to use the existing mic in the headliner and use the existing wiring and antenna hardware. Since I was also installing a GPS system, I opted to get MB part # 163 820 06 75, which is the combo GPS/cell antenna that made its debut with the 00MLs. The cabling in the 99s (and the 98s, I suspect) is RG-58U coaxial cable, which support analog, and the various flavors of digital (i.e. CDMA, TDMA, and GSM). Since I have a 99, I also had to get MB part # 163 820 12 89, which is the complement to the combo antenna. The antenna muxes the GPS and cell signal together, while this part splits them back out again. This splitter took forever to hunt down with zero help from MB--the only reason this project was completed was because of great help from my dealership's parts guy and service tech. For model year 2000 and beyond, you already have the splitter and it is located behind the radio--astonishingly, it is clearly labeled "splitter".

Installing the antenna is a no-brainer--the biggest challenge is that it comes with an integral stick-on gasket to keep water etc out of the roof entry, so you get only one shot to install the antenna. Installing the splitter is a little trickier--read-on...

In my ML, the cable run from the antenna terminates behind the radio and is then, with an extension cable, is extended to a spot under the bin in the center console. Behind the radio is also a 10-position RJ connecter with also ends under the bin in the center console. For my purposes, this cable is irrelevant, except, taped to it is the cable that is connector to the headliner mic.

This is where we enter connector hell....

The cable run from the antenna and all the connections on the splitter use what I believe is termed a SAP connector. The only problem with this is no one on this side of the friggin planet uses SAP connectors, so finding parts to make cables etc was a royal pain. My suggestion is to go to a place that installs Nokia phones (avoid the chains, like Good Guys, they are useless and/or hostile) and buy convertors that will convert the connections from SAP to something more prevalent like mini-UHF. If all else fails, you can order convertors from the Nokia web site to convert from SAP to mini-UHF--the part number is AAC-1 (aka "RF Adaptor"). For my install, I have the antenna lead feed into the splitter, then I have a feed from the splitter to the Nokia cradle. If you are not doing the GPS foolishness, then you can connect the antenna feed directly to the cell phone cradle. The antenna feed and the cable from the cradle both terminate in a female SAP connector so you would need to address the "gender" issue. BTW, if you are not going the GPS route, you can also order MBs regular cell phone antenna which is a heck of a lot cheaper.

Connecting to the cable from the mike depends on the financial disposition of you ML, I guess. My ML is bought and paid for, so I simply snipped off the connector on the cable to the headliner mike, snipped the mike of the cable supplied with the Nokia kit and and used gel-caps to connect them together. Voila--works great. If you want, you can use mid-line taps like Scotchlok to preserve the MB harness. It will work, but will probably be noisier than the gel-cap route.

I did not completely tie the Nokia into the Alpine (yet) because there is no clean way to do it yet that actually makes things easier to use--there are some parts coming from Alpine later this year that I will probably install that will offer tighter integration between the phone and the Alpine unit. The only integration I have implemented so far is that I have the Alpine wired to mute when a call is received or placed. I have the Nokia cradle using a separate speaker (not the one from the kit) which I have mounted low down on the driver's side of the center console.

Finally, I have installed a 2.5mm headset jack into a discrete spot on the center console, so I can have extended conversations with better fidelity. The headset connector on the Nokia CARK-91 car kit is an RJ-45, so basically, I dug up an old ethernet cable and ran if from the car kit base to a spot in the center console, snipped the end off and wired in to a 2.5mm jack. I cannot find my notes right now, so I cannot give you exact pinouts, but if someone is interested, I can dig them up and post them.

So how does it work. I have only been testing it for a few days, but I would say it is worth the effort. Reception is awesome. I live in northern CA in the Bay Area and spend a lot of time on the road driving up to Sacramento. I can name all the spots where I would drop to 1 or two bars. With the kit, I am at four bars almost all the time.

Sound quality using the speaker and headliner mike is what you would expect in a truck. Listening to the other person works great, they are the ones that have to deal with mediocre quality because the ML is so noisy at speed. I tested the MB headliner mic and the Nokia mic and sound quality is comparable.

I am guessing a non-MB StarTAC install would look much the same. One piece the Motorolas seem to need that the Nokias to not is a Linear Compenstor which seems to be akin to a smart booster. I do not have an MB part number handy for this (sorry).

So, I finally have a chance to tell you about the install of the Alpine Nav System. This is a list of what I shoe-horned into my 99ML430:

Alpine CVA 1005 Multimedia Center
Alpine NVE 851A DVD Navigation System
MB Quart RKC 113 Coax speakers (rear doors)
MB Quart PSC 213 Component Speakers (front doors)
JL Audio 8W0 subwoofers (qty: 2, in rear hatch)
Zapco AG360 amp (to drive MB Quarts)
Zapco AG150 amp (top drive subwoofs)

The install was actually pretty straightforward.

The CVA 1005 cones in two pieces: The controls and display which fit in a single DIN slot and a back-end which houses the amp and connectors (speakers, sources, nav, etc) in an aluminum unit about 8" x 10". I installed the display in the lower DIN slot (usually filled with the storage bin) so the display would not block the vents when it is opened. I then ran the wiring harness to through the center console (see previous post about disassembling the center console) and mounted the amp on a piece of MDF board under the driver's seat in the space once occupied by the Bose woofer. Given a choice, I would rather have mounted the back end on the firewall behind the dash to keep the wiring runs smaller (there is space), but my ML disassembly skills are still not advanced enough to attempt that. :)

The connections for the CVA are pretty standard except that it needs a connection to the brake lead and the parking brake. The reason for this is to prevent DWS incidents: a portion of the controls are not available while the car is moving. To access them, you have to go through this little dance of pressing the parking brake and the foot brake in a certain sequence.

The parking brake is simple enough:
1. Remove the black trim above the driver's footwell by removing the two black screws at the leading edge (where it connects to the lower dash) and the two washer/nut thingies [that's the technical term] behind the brake pedal.

2. Pull the trim piece gently, but firmly down and toward you.

3. If you feel up to it, you can disconnect the connector for the computer, which is on your left, by the door hinge, or you can leave it connected and just pivot the trim panel out of the way.

4. There is a pin switch located at the top of the foot brake pedal with two wires coming out of it: light brown and dark brown--tap into the light brown wire with your preferred method--I use Scotchlok type mid-line taps.

The foot brake was a royal pain in the a**. I could not make sense of the signalling coming out of the switch attached to the brake pedal, so assumed it was some sort of digital feed and not useful for my purposes. Since I had the back-end installed under the driver's seat, I ran a connection to the stub harness for the trailer hitch located in the cargo area. The brake lead is an orange wire.

The only other connections hiccup was getting a convertor for the AM/FM antenna lead. I just snipped off the old connector and crimped a new one into place, but if you want to preserve the old connector, there are convertor plugs available.

The Nav unit was also pretty straightforward. Since there is a ton of room, under the drivers seat now, I installed the unit there too. It ties into the CVA 1005 with a single cable and then has its own harness for power, etc. The Nav unit needs three special connections: vehicle speed (VSS), reverse sensor, and parking brake signal. The VSS is only available through the CAN Bus Adaptor (see previous post on CAN Bus adaptor pinouts and installation). The reverse signal is available from either the CAN Bus adaptor, or by tapping into the lead for the reverse lights. The parking brake signal lead is obtained the same way as it is for the head unit.

Some thoughts about wiring....

First of all, the wiring is VERY nicely done in the ML--neat and well protected. There are three wiring trays in the ML (that I found). One runs down the left side of the center console and ends a little past the end of the front seat. There is also a wiring tray on each side of the car that runs just to the inside of the door jamb. The driver's side tray is pretty well packed, while the passenger side is almost empty (just the hose for washer fluid).

There is a lot of redundancy in the two Alpine wiring harnesses (head unit and nav unit). If you do your own install, I would advise you to terminate as much of the nav unit's harness on the head unit harness, so you can minimize the amount of wiring you need to un/fish/terminate/troubleshoot.

The trickiest part of the Nav install was the antenna. I use the Alpine provided antenna to test the install, but I ultimately wanted to use the combo cell/GPS antenna that became available with the MY00 MLs. Installing the antenna takes about 30 sec--it simply screws into place. The only caveat is you get only one shot: the antenna has an integral adhesive gasket to keep water out of the hole in the roof where it attaches--one the adhesive catches, it ain't goin' nowhere. Since I have a 99, doing something with the antenna fed was a little trickier. I needed MB part number 163 820 12 89, which splits the antenna feed into a cell feed and a GPS feed. The widget is standard on MY00 and later. Finding this part number was a two week saga which I won't go into here. Anyway, this splitter uses SAP connectors, so you have to deal with that. I used SAP-to-mini-UHF convertors from a place that installs Nokia phones (Nokia uses the same sort of connectors). I connected this feed to the nav unit.

Since I have been living with the Alpine unit for a couple of weeks, I thought I would offer some thoughts.

Overall, it is awesome--the GPS works great--it is accurate and fast. It is DVD based, so I get the whole US on one disc. The route selection works well--it has only sent me on a couple of goose chases and on more than one occasion found new/faster ways to get to places I often visit.

The screen resolution on the Alpine unit seems higher than on the MCS.

The unit has a detour function to re-route around construction or congestion which is great in the Bay Area--the unit also does an automatic re-route if you stray of the path.

Destination selection is very versatile: address, intersection, address book, recently visited places, phone number (a reverse lookup), and points of interest (i.e. restaurants, hotels, ATM, etc).

The Points of Interest database seems to be very comprehensive and access/search speed is reasonable (i.e. find me the nearest Chinese restaurant)--although the interface is kinda cumbersome.

Accuracy is good. I have had the antenna on and off during the course of the install, and even after a couple of days of pure inertial guidance (i.e. only the internal gyroscope and speed sensor), the unit was only off by a few yards. The system self-calibrates, so the more you drive, the, the more accurate it gets.

My biggest complaint is around screen brightness--it would be nice if it had a sensor and adjusted brightness according to ambient light levels--right now, if I turn on my headlights in the daytime because of inclement weather, the screen dims and it becomes really hard to see--I can turn off the feature, but then the screen is really bright at night.

Take care,

O

Omar Sultan
Business Development Manager - Service Provider Field Support
Cisco Systems, Inc
408/527-8144