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Moron95M3
07-19-2013, 10:25 AM
***************EDIT* Mod has been finished. A DIY 3.5mm jack not using the tape deck inputs. Also replaced the burned out bulbs and swapped faceplates with a nicer nonfunctional unit.

Read farther down for more :)







Ok guys, I posted a bit concerning a radio stuck in 'code' (won't go to 'wait' and wasn't accepting the correct code).

So, rather than just replacing my old radio, I figured I'd combine them both to get exactly what I want. Here's the start:

What I have:
CM5903L from my car (220k) with worn out buttons, a dead right hand LCD Screen (one bulb) and LCD bleed through on the left.
CM5903L from another car in much better shape, but locked in 'code' mode and also has some bleed through on the right hand side.

What I want to have:
One good CM5903L. Limited bleed through, all lights lit up.
Also want a 3.5mm aux input hooked up to automatically trigger when something is plugged in (This is where I differ from the 'dummy' tape method).

Here are some links I've found that have helped thus far:

How to fix a dim display (however I think it's for a C33/43 as mine is slightly different)
http://forums.bimmerforums.com/forum/showthread.php?251722-How-to-fix-your-e36-dim-radio-display


How to Add Aux into a C43 (tape deck differs from the CM5903L).
http://forums.bimmerforums.com/forum/showthread.php?1886405-DIY-E36-Aux-in-with-C43-headunit


How to add aux into a C33 (which has the same tape deck).
http://www.m3forum.net/m3forum/showthread.php?t=239069



Let's get onto some pics. I will update this thread as I continue.


Here's what I started with. No pics of the right bulb being out behind the LCD but you can imagine that.
https://sphotos-a.xx.fbcdn.net/hphotos-ash4/1004794_888251474827_294391970_n.jpg




Now I took my other better radio and started to disassemble. I wanted the faceplate for my radio so I started by taking the face off and the top plate of the radio.

Face plate is pretty easy, two screws on each side and then a few tabs that you need to push in to pry it off. (remember to pull your volume knob off first)
https://fbcdn-sphotos-g-a.akamaihd.net/hphotos-ak-ash3/1069292_888251814147_295360386_n.jpg
https://fbcdn-sphotos-f-a.akamaihd.net/hphotos-ak-frc3/988636_888251340097_1245687861_n.jpg


The top cover is pretty easy to remove also, it's two screws in the back of the plate, then just pry it up.

Here's the 'new' cover plate with the top plate removed.

https://fbcdn-sphotos-a-a.akamaihd.net/hphotos-ak-ash4/270607_888251794187_1390495430_n.jpg

and the top plate off (see the two screw holes)
https://fbcdn-sphotos-b-a.akamaihd.net/hphotos-ak-ash3/600587_888251993787_961966317_n.jpg


Then I pulled the tape deck out. It's just 4 screws and yanks out. The connector is under it but just pulls out.

https://fbcdn-sphotos-h-a.akamaihd.net/hphotos-ak-frc3/1069338_888251953867_1739006665_n.jpg

http://i944.photobucket.com/albums/ad286/mtnbike420/E36%20Aux%20in/4.jpg

And here is just the tape deck:
https://sphotos-b.xx.fbcdn.net/hphotos-ash4/228997_888251898977_1382853775_n.jpg




Now I went on with taking out the LCD display. Unfortunately for me, it's just one screen so either one I use will have bleed through :( Although I'm going to a junk yard tonight trying to get another one or two CM5903's.

Here's the display: (this is the 'better' radio but has more bleed through)
https://sphotos-b.xx.fbcdn.net/hphotos-ash3/943617_888251549677_939327699_n.jpg


It has one ground you need to unsolder. You can actually pull the display off before de-soldering
https://fbcdn-sphotos-h-a.akamaihd.net/hphotos-ak-frc1/1003737_888251754267_155823740_n.jpg

https://sphotos-b.xx.fbcdn.net/hphotos-prn2/1069369_888251769237_785273909_n.jpg


I pulled the 'good' radio's display and found there are 6 metal tabs you need to de-solder to get to the bulbs under the LCD. I am assuming one bad bulb is the issue with my current radio and am stealing them from this one.

I desoldered half the tabs and bent the display forward so I could get to the bulbs. I desoldered those also and pulled out the bulbs.

After bending the display outward. (see the two bulbs)
https://fbcdn-sphotos-g-a.akamaihd.net/hphotos-ak-prn1/73340_888251644487_240606396_n.jpg

bulbs:
https://fbcdn-sphotos-e-a.akamaihd.net/hphotos-ak-prn2/1069238_888251604567_1941278676_n.jpg.




For fun, I put the display back together, but it didn't quite sit right (there are two plastic guide pins that align the lcd to the board, and one didn't line up happily so I think only 1/4 the ribbon cable was making good contact. When I plugged it back in that's about what I saw. (start of the work 'CODE' up top).
https://sphotos-a.xx.fbcdn.net/hphotos-ash4/1004793_888251569637_797151216_n.jpg


So thankfully that was just a test, and for the other radio I'll be much more careful when I reassemble.




So for my LCD screen fix, I still need to install a good bulb, and try to find a better display somewhere...




Now to the tape deck and the aux input: Most aux input threads do something to fake a tape being inserted, however I want to be able to keep the function of the tape if for some reason I want to use it.


So here's what is going on. When you insert a tape, the tape physically pushed an arm that lifts up on a little plunger switch. This switch (with no tape) is a closed circuit. When you insert a tape it's open circuit. So I wanted some way of breaking the circuit when you insert a 3.5mm jack into the aux port.
(y'know how when you plug headphones into your computer it automatically knows not to play out the speakers? That's a 5 pin audio 'switching' jack. Which I'm going to use to do what I need to above.
$3 at the shack.

https://fbcdn-sphotos-h-a.akamaihd.net/hphotos-ak-ash3/1011979_888251414947_2046339881_n.jpg
https://fbcdn-sphotos-d-a.akamaihd.net/hphotos-ak-prn1/31465_888251355067_1214926561_n.jpg


https://fbcdn-sphotos-b-a.akamaihd.net/hphotos-ak-ash4/1012355_888251380017_1082256670_n.jpg


Now here's the fun part.

The circuit needs to be open for the Aux or tape. So I need to break that circuit somehow using this switching jack. But the jack will close the switch when something is installed. I think I can find a relay that is always closed and opens when powered that I'll be able to use here. I'll also need power then to run to the switching jack and have it come back to the relay. I'm going to draw it up and can post later.

Overall I think it can work. I'll need to find another place though in that circuit to add this relay. That's the only thing I'm worried about. It would be 100x easier if the circuit need to be closed for aux/cassette and open for FM.

Last thing I'm not sure of is how to get it to switch from Aux back to FM. I'm not sure if just closing that circuit (removing the 3.5mm plug) will automatically force it to radio or not. (I.E. when you hit 'eject' is that just forcing the tape out and when the switch closes it goes back to radio? or does something occur when you hit 'eject' that changes it back to the radio? Hopefully the first way as that's what I'm trying to do)


For the actual audio signal, I'll be doing as the C33 shows in the DIY (solder ground/right/left to the Cassette board).


More to come hopefully tonight! I need to get a few relays and a new soldering iron (long story, my current one is shit) tonight from the shack. Hopefully I'll get something cool out of all this!

jjjjjjj
07-19-2013, 11:45 AM
Nice writeup!! This is one for the purists out there

Moron95M3
07-20-2013, 11:43 PM
ok, brief update.

Got both bulbs replaced on my old LCD screen. Tested and works great! (still bummed I have some bleed through)

Soldered in the aux in mod. Easy and works great also. Quality is better than headphone jack->tape converter.


Tried something with the 'switched' jack. I'll explain more later but was able to get the player to go straight to 'tape' when I only plugged in the 3.5mm cable, but it would only play one channel and keep switching between 'tape 1' and 'tape 2' so it was constantly interrupting itself.

The first problem of the one channel only I know what's up, but I don't know why it's switching between 'tape 1' and 'tape 2'. Any help here would be great!

slocar
07-21-2013, 12:55 AM
Props for the hard work and wanting to keep the OEM radio!

I did the same when I got the car ... went through the trouble of re-soldering to fix the dead LCD, then I wired in an aux cable instead of the tape ... but I'm over it all to be honest. I want ipod control, I want to be able to make an mp3 cd with 300 songs and put it in the dash instead of shuffling CDs int he changer ... so I just ordered the harness off ebay and will be buying something like a Kenwood KDC-352U here in a day or two. It has variable colors so it can be matched to light up amber, and it's black and stock-ish looking so I don't really mind any more.

Moron95M3
07-22-2013, 09:17 AM
yea slo, I figured I'll be in that boat...But I CANNOT find a HU that I like, that looks oem-enough. I also use the cd changer, and don't really want to fuss with upgrading to an Ibus changer and CD43/etc.


New update, I think rather than hacking the tape input, I'm going to use the 'pass through' switched jack and tap it to the CD changer. This way, to get the AUX to work, I just hit 'CD'. The tape player stays unchanged. (not that I'll use the tape player, but I like having the option)

Anyone know if the CD changer plug (w/L and R + and -) is line level or speaker level? I'm guessing it's just line level and I can tap into it but I want to make sure it's not speaker level (the R+, R-, L+, L-) makes me wonder that it's speaker level.

- - - Updated - - -

reading this makes me think it's line level..which will work perfectly.

http://forums.bimmerforums.com/forum/showthread.php?331367-Pinout-to-CD-changer-connector-on-back-of-E36-radio

- - - Updated - - -

one more quick update. Not sure if this matters in finding if the signal is line or speaker level, but all grounds (ground, L-, R- are the same; continuity tested).

- - - Updated - - -

Moving onward!
http://forums.bimmerforums.com/forum/showthread.php?2017843-Is-the-OEM-E36-CD-changer-providing-line-level-or-speaker-level-input-to-the-HU&p=26641639#post26641639

- - - Updated - - -

Few more pics for random interest. (looking at CD changer pinout)

Haven't taken this out before...

https://fbcdn-sphotos-a-a.akamaihd.net/hphotos-ak-frc3/998212_889449878217_1561840905_n.jpg


Changer pin out

https://fbcdn-sphotos-g-a.akamaihd.net/hphotos-ak-frc1/1003314_889449848277_28630948_n.jpg

changer and main harness:
https://fbcdn-sphotos-b-a.akamaihd.net/hphotos-ak-frc1/1004808_889449898177_565410115_n.jpg


Match up with this I think...
http://www.europeanautosource.com/images/vendors/dice/wiring/pinout_mph.jpg
468058

- - - Updated - - -

so this is the plan...

http://i799.photobucket.com/albums/yy275/MTU4x4/null-96.jpg (http://s799.photobucket.com/user/MTU4x4/media/null-96.jpg.html)


Using something like this as a jumper harness.
http://i.ebayimg.com/t/2-54mm-Pitch-10-Pin-Wire-IDC-Flat-Ribbon-Extension-Male-Female-Cable-12-Inch-/00/s/MTIwMFgxNjAw/z/C0IAAOxyaRZR2-So/$T2eC16NHJGIFFod7r,7fBR2-SoW0ng~~60_57.JPG

Moron95M3
07-22-2013, 09:44 PM
Well I got it to work! Still have the tape player and CD changer functionality.

So here's how I did it. As I posted above, the 5 pin 3.5mm jack allows the channels to be 'pass thru' until you insert a plug. This mechanically opens the switch and just provides the 3.5mm plug signal rather than whatever else it had been seeing.

So I decided to hack into the CD Changer harness. Although rather than cutting/splicing the OEM harness, I created my own 'jumper' harness. This was a bit of a PITA. I found out the CD changer plug is a 10 pin, 2x5 connector. A typical USB cable is 2x5 but only uses 8 pins. It's also tough to find one (especially if you're impatient like me and don't like waiting for Amazon).

I took a trip to the local computer place, and he was able to yank out 2 old USB cables and gave them to me. He didn't sell them new as it's old tech I think. I had enough pins to make 2 10 pin connectors, but had both female ends. Easy answer is cut ~3/4" solid wire and make your own pins to make one side male. Tough to line up though :/

The harness was a bit of a mess (as you'll see) but it simply is what I have drawn above.


Cat is NOT helpful.
https://fbcdn-sphotos-b-a.akamaihd.net/hphotos-ak-ash3/944269_889725555757_2112041615_n.jpg


you can see the old harness on the left. See the solid copper wire as pins. Then that wraps around to the new HU input (aux pulls off of that and goes down by the sunglass holder).

https://fbcdn-sphotos-c-a.akamaihd.net/hphotos-ak-ash4/1001025_889725500867_1206148022_n.jpg


https://sphotos-a.xx.fbcdn.net/hphotos-ash4/1000524_889725465937_295085782_n.jpg



Here's the Aux input (after I taped it all up)
https://fbcdn-sphotos-g-a.akamaihd.net/hphotos-ak-ash3/45886_889725431007_1694009313_n.jpg

Drilled the hole in the sunglasses holder, and mounted everything.

https://fbcdn-sphotos-a-a.akamaihd.net/hphotos-ak-frc3/988652_889725376117_1414254890_n.jpg






And got the bulbs working and the new faceplate on the old radio. Still working on getting a new display without bleed through :(

https://fbcdn-sphotos-h-a.akamaihd.net/hphotos-ak-ash4/1069790_889725341187_1997351979_n.jpg

Moron95M3
07-23-2013, 01:52 PM
clean DIY for Aux Input here:
http://forums.bimmerforums.com/forum/showthread.php?2018366-DIY-for-Aux-Input-%28not-using-the-tape-deck%29&p=26647541#post26647541

jagerking
07-23-2013, 02:28 PM
That is sweet, buddy. :handclap for ingenuity and execution.

Moron95M3
07-31-2013, 09:31 PM
well...found a local guy that would ship me just a good display from a non-working radio.

All buttoned up! I'm super happy!

http://i799.photobucket.com/albums/yy275/MTU4x4/null-107.jpg (http://s799.photobucket.com/user/MTU4x4/media/null-107.jpg.html)

t42
11-30-2013, 04:26 PM
Great thread and great DYI! Thanks!

Now all we need to find is someone to make and sell on eBay the jumper cable / switching headphone jack assembly! Guess that would make this a PnP project rather than DYI! But thats ok w/ me!