Chrysler - Mitsubishi RX-696BH CD Changer Controller
In the mid nineties, Chrysler began to offer cassette decks that controlled CD changers. I've already given you a look at one of the first decks with this feature in the cloud-car-specific Alpine built unit denoted by the sales code RBS. Today, I'm giving you the chance to look at Chrysler's more mainstream answer to CD changer control in the Mitsubishi RX-696BH.
This particular unit came from the dash of a 1999 LHS, but it could be found throughout the late nineties in many Mopar vehicles. It is most easily identified by the presence of the mode button next to the power button, and by the compact disc operation labels on the preset buttons. Otherwise, it looks a lot like the deck that preceded it, the Infinity III.
Like the Infinity III that came before it, this deck bears the supplier code of Mitsubishi, 28046. Also like some other decks Mitsubishi made for Chrysler, this one helpfully bears the pinouts of the main connectors right on the label. A date code of 0606 suggests that this particular deck was made sometime around the middle of 1996.
It has a lot in common with the other popular deck of that era, the CD/cassette combo deck. Though this deck lacks a built in CD player, it makes up for it with that changer control and a five band equalizer. Otherwise, as we are about to find out, there are a few small internal similarities between them, along with the ability to get the time by pressing the volume knob, whether the ignition is on or not, and a nearly identical cassette assembly.
There is a single screw near the top center. This is the only screw that holds the top cover on... make note of that for later.
This is the bottom of the deck. The only two screws you see here, arrowed in red, are to hold on the front panel carrier assembly. We'll worry about those in a little bit.
The side panels. The red arrows indicate screws that hold on the side panels. You do not need to remove them, ever, to work on this deck. As you are about to see, this deck is actually very easy to work on. It is modular in construction.
The blue arrows indicate the screws that hold on the faceplate and faceplate carrier.
The back panel, and a barrage of arrows. The blue arrows indicate all the screws that hold on the back panel, which also functions as the heatsink for the unit. All of these screws are longer than the others in the deck, save one.
The yellow arrows indicate two built in spade terminals. These are used to connect your vehicles Infinity relay ground wire to. That's the extra male spade connector you might have seen in the dash of your vehicle. Earlier decks relied on a separate ring mated to the main ground bolt to provide this terminal, and it's only natural that later decks started providing this functionality natively.
The green arrow indicates the CD changer port. Note that this is not compatible with the earlier slave CD player that was available in the late eighties and early nineties. You need the later Alpine built six disc changer to mate with this connector, though you can also get interface boxes from Precision Interface Electronics (PIE) that allow auxiliary devices and even iPods to work here too.
Finally, the red arrow. This is a two pin connector that accepts a CCD bus connector on the vehicle harness, allowing the car's computers to talk to this deck. This allows someone with a scanner to access trouble codes stored in the deck, as well as the interface of steering wheel controls and a few other vehicle features like display dimming and brightening.
The first thing we're going to do is take off the faceplate. Remove the four screws, pull off the EQ, volume, and joystick knobs; and just unclip and pull it off. You should get this view.
Now, this deck is missing all of its illumination bulbs, but they are the same 12V 3mm grain of wheat style bulbs in twist lock bases that all Chrysler decks of this vintage enjoy. Please see my Infinity I guide for more information on replacing these bulbs.
On this deck, if you want to replace the bulbs, the faceplate PCB must be removed first. De-solder the twist tab indicated in blue, and then twist it horizontally as in the picture to release it. Then, remove the two screws indicated in red. From here, just hook your thumbs into the cassette opening to grab the board, and pull it forward. It should pop right off, secured from here only by two connectors.
Here is the faceplate PCB removed from the deck. The board must be removed from the unit to enable removal of the mainboard later on, but you don't necessarily need to remove it from the metal carrier itself. You can leave the board in place if you have no need to work on it.
Before we go on, here's a close-up of the button assemblies. One has been taken apart for your reference. These often get dirty, or the green contacts themselves break, requiring some attention. Yes, these are the same button switches found in the square faced combo deck of the day. To clean them, remove the metal clip, pull the plunger out, and gently tweeze the green contact itself out.
From there, I like to stick a little piece of pencil eraser on the end of a jeweler's screwdriver. Then, I stick that screwdriver into the button housing, scrubbing the metal contacts with the little piece of eraser. I then gently repeat the exercise with the little black area on the bottom of the green silicon button contact itself and re-assemble the button. Repeat for all other buttons.
This deck, like most other Mitsubishi built decks, is known for developing cold solder joints, so I'll show you how to get it apart to work on them.
First, we'll remove the tuner module. Removing the top cover, you should see this view. Red arrows indicate the screws holding the module in. Remove them. Note that the one at the antenna connector is a long one, like all the other rear panel screws. Unplug the connector indicated in yellow.
Then, the tuner board just pops straight up and off.
Joined with only two connectors as it is, the tuner module could not be easier to remove. But there is work to do before we can get at the solder joints on this board.
See the red arrows? They all indicate metal twist tabs you need to un-twist. Do that, and then turn the whole shebang over.
Some more red arrows here indicate several solder tabs you must de-solder now to release the circuit board.
Here's the board without the metal shield. Note that there are a lot of surface mount components to work with, so be careful while touching up the solder joints here. When done, mount the board back on the metal shield.
Moving on, we'll start looking at the mainboard. It's the next logical step, as this deck comes apart from the top down. You must remove the mainboard before you can get at the cassette module.
Note the two screws arrowed in red - you have to remove those to release the mainboard.
But before we even do that, we have to remove the faceplate carrier. Remember those two screws you saw in my picture of the underside of the deck? Remove those. The carrier is then only clipped on from here, and the rotary encoder assembly (volume knob) can remain in place as you unclip the carrier on both sides as shown and then pull it straight off.
Before we go on, observe the red arrow. This is the lamp that illuminates the cassette bay - it is yet another one of those grain of wheat bulbs in a twist lock base. Don't forget about it when replacing bulbs... you can get to it to replace it as soon as the tuner module comes out.
Now, it's time to remove all those screws on the back panel, and remove the back panel as shown. We are almost able to remove the mainboard now. Disconnect the ribbon cable arrowed in red - this cable runs to the cassette module.
When you've done this, pull the mainboard straight up and out.
Like so. It's very easy to work on the mainboard's soldering joints from here, but I'm going to go just a bit further and show you how to get at the amplifier chips.
See that daughterboard with the black and gray connectors on them? Pull that straight up and off. It is joined to the mainboard with connectors at the bottom, and should come out without too much fuss.
Now, we need to remove that long metal bracket that runs across the back of the PCB. Turn the board over.
The red arrows indicate the solder joints to de-solder to allow removal of that bracket. Once you have done so, you will find that they are actually really small twist tabs... twist them to line up with the slots in the board. Then, pry that bracket up and off the board.
Here's a look at the three parts of the mainboard assembly: connector daughterboard in front, metal bracket in the middle, and the board itself in back.
Both amplifier chips are Toshiba TA8233H. These are very common in the mid to late nineties Chrysler decks, so finding replacements shouldn't be too hard. Make sure all solder joints below these are in good shape... solder joints often fail first under the hottest components.
Finally, we'll look at the cassette module. Remove the middle plate from the unit and set it aside, like so. The plate should come right out - it is only clipped in once you take the mainboard out.
This is why you do not need to remove those other side panel screws - look at the oodles of space in there. You can remove the side panels if you wish, but it's not necessary at all.
Some of you may be experiencing deja vu at this point. Perhaps you've taken apart a Mitsubishi CD/cassette combo deck from the mid nineties and something looks familiar. Well, you're getting that feeling for good reason - the cassette module is practically identical. Indeed, I have a combo deck tape module right beside me, and the only difference I can spot is a tiny two pin connector that was not used in the combo deck for anything. It is likely the modules are swappable, but I haven't tried it.
From here, you can already clean the tape head, capstans, and pinch rollers. Take a swab moistened with isopropyl alcohol, get in there where the blue arrows are, and scrub those parts really well.
Removing the cassette module to get at the cassette belt couldn't be easier. Observe the four red arrows - those are the mounting screws.
And here we see that replacing the cassette belt itself is easier than putting on your socks in the morning. The belt is freely accessible as soon as the module comes out.
I've pointed at one last area of interest using the blue arrow. Like most other nineties Mitsubishi built decks, this one uses reel sensors to keep track of whether or not the tape is playing. The blue arrow indicates one of the reels, on the back of which are some reflective strips, as you can see in the picture. A beam of infra-red light is bounced off these reels. As long as the reels are turning, the computer sees a bunch of light pulses and thinks, "ok, the reels are turning, so the tape is playing." When the end of the tape arrives, the reels stop turning. The computer sees no more pulses and knows it's time to play the other side.
But these sensors can fail. If they do, even if the tape is in the middle of playback, the computer thinks the reels aren't turning. So, it reverses. And reverses. And reverses. Over and over this happens, until you hit the eject button or change operating modes. These are not serviceable parts, so at this point it's best to go find a replacement cassette module.
Now that we've had the deck apart, there's only one thing left to do - put it back together. Good luck. It won't take much of it to re-assemble something this easy to get apart, I'm sure.
|General Chrysler-related radio and stereo articles at Allpar:|
|CD and DVD systems (stereos have a three-letter code on the face plate)|
|Tape and tape/CD systems|
|From here to Infinity|
|Classic systems (before tape decks)|