Anyone have any experience using UConnect A/V systems in recent Chrysler (or Doge or whatever) vehicles? I'm considering trading in my 2006 Charger for a 2012 or 2013 model, but one major sticking point is that it seems to have become even harder to integrate aftermarket audio. In particular, because many functions like climate control, heated seats, etc. are integrated into the OEM A/V system, I can't really yank the whole thing out, and because there's not enough room in the dash for another DIN, integrating my Empeg is probably going to be a giant hassle involving AUX input, a display extender, etc.

Just curious to hear if anyone has used these Uconnect systems, or tried to do an empeg install in a vehicle that has them.

No, but get the STR8 and let me take it for a ride.

I have a 5.7.

I figured the 6.1 would be a bit much for the wife.

Heh. As much as I'd love to have an SRT8 in my garage, the 5.7 is more than enough for my daily driving. I am actually going to test drive the 3.6L V6 to see if the new 8-speed transmission makes a big difference. I'll definitely miss the torque of the V8, but the possibility of 31 MPG highway is at least worth looking into.

I just wish the manufacturers would stop making it harder and harder to do custom audio installs. The thought of living without my empeg is making me seriously consider trading in for a used 2010 or so Charger instead of buying new.

I rented a v6 (I think it was the 3.6) for a week to see if I'd like the car in general and I found the v6 to be very underpowered. Now that was not an 8 speed but in my opinion no matter how many speeds you have it’s not really going to help power. Now fuel economy is a different story. I’ve also heard the reliability of the v6’s are not that good and with 8 speeds that a lot of things to break

Could you possibly put the empeg in the console or perhaps use a display extender? I have my DVD, CD, HD Radio, head unit in my Jeep’s console. While inconvenient it does fit and is stealth.

Yeah, a display extender purchase might be in my future. The thing is, I'll end up spending all that money to buy the display extender and integrate it just to get the empeg as an AUX in source. I had that arrangement (minus the display extender) in my Mustang a while back, and I didn't like it as much as having the empeg as the head unit. Unfortunately nobody seems to have cracked that nut yet for the 2012 systems, at least not that I've been able to discover on Chrysler forums or by talking to local radio installers.

I'm in the same boat with my car. I'd like to preserve the stock radio and make use of my empeg without having it be an auxiliary device. I'm pretty sure I lose climate controls if I remove the stock HU, so that's why I'm leaning towards dual op.

I'm toying with the idea of putting both devices on the speaker line with an A/B switch of some sort to choose which device is allowed to output. I guess I'd have to route the stalk interface through that switch as well.

Really, I'm just making stuff up and have no idea whether this is really a viable option.

You might be able to hook a 12v solenoid up to the amplifier turn on wire from the empeg (blue wire) and have the solenoid disconnect the speaker wires from the factory radio and connect them to the empeg amp.

Then switching the speaker’s connection between the factory radio to the empeg would be as easy as turning the empeg on.

That would require two sets of power amplifiers. And any switching system would have to handle the full DC wattage of what you're sending to the speakers. Most switching systems I've seen are line-level, i.e, before the amplification stage, such as the Sony XA39-II mentioned in the empeg FAQ.

Why specifically don't you want it to be an aux device?

I know you were asking Caleb, but from my perspective, using the empeg as an aux device means it's basically just an iPod with a much better UI. The empeg as a head unit lets me do everything (MP3, AM/FM, and in my setup, XM and my cell phone on the AUX input) with the same controls, the same interface, etc. I know there are drawbacks (no Bluetooth phone integration, hassle integrating steering wheel controls, forced to multiplex the aux input, etc.) and maybe part of it is not wanting to let go of the empeg as the centerpiece of my system... But I really question whether I'll want to go through the expense and hassle of integrating it if it's just going to be serving MP3s only -- at that point I may as well just use my phone as an aux device -- then I don't have to install the wifi router to be able to sync my collection, I can just use Google Music on my phone.

I guess it boils down to "go big or go home." The point at which the empeg is just a big hard drive with an RCA output is the point at which I question whether it's worth tearing up a new car to install.

I don't have a problem with going to a lot of trouble for that. :-)

Yeah, normally I'd be with you -- after all, I went through the trouble of installing a wifi router in the trunk, integrating the tuner module, an XM receiver and an AUX-in multiplexer, etc. and would gladly do the same in the new car if I thought it would work well with the factory system. But because there's no room in the dash on the new car, it'll mean shelling out $400ish on a display extender, mounting the empeg in the glove box, and finding a place to mount the external display. Then who knows if I can integrate the steering wheel controls without interrupting their connection to the OEM system.


Don't get me wrong. I can't count the number of things I would miss about the empeg if I used some other solution for MP3s in my car -- I was strongly considering getting a used car instead just so I could keep the status quo -- but if I do that, I'm really just putting off the inevitable. And I'm not ruling out going the aux-in route when/if I trade my car in... But the list of pros and cons is starting to become much more even than it used to be, and that makes me rather sad.

No help from me on the issue, but i've kind of accepted that my empeg will be retired from in car use once my current car dies/get replaced.

So instead of a 2012 Charger, get a '68 Charger and spend the extra money putting in modern suspension, steering and brakes.

Of course you'll be crying every time you visit the pump, but hopefully your empeg will cheer you up as you drive away.

Except 68 Charger in good shape might be about twice the price.

One of those things I should have stocked up on in the 80'x

It's hard to "stock up" on cars... I tried it... they're big.

I guess nine cars, one dump truck, one van and an RV are enough.

But I remember not buying a 1970 (I think) GTX with a 440 and air grabber hood for $800 because I thought that was a lot. There also was a rust hole on the driver’s side quarter panel. I think I could probably sell it for more than $800 now.

Then on another deal after I bought a Dana 60 and four speed for $50 from a guy I worked with he was going to give me the body they came out of (a 68 Charger) if I would haul it away. I thought I had enough junk. There again, wrong thinking, you can never have enough junk.

I max out at five cars and a truck. All '70s convertibles, and a 1930 AA flatbed. I miss them all.

Oh, and 9 motorcycles...

Sadly we're down to only six bikes here right now. Pedal Power!

That sounds like fun. I almost bought a Kaiser deuce and a half at an auction last year. I would have sooo much fun putting huge ruts in the field with that. But I really couldn’t justify any other use for it.

Down to six motorcycles. I sold one Sunday

I'm down to just a bicycle since my Jeep's been dead for several months. My three year old rides on the handle bars and my 18 month old rides in a baby seat on the back. Guess I'll have to strap the newborn to my chest.

Nah... your wife can carry the newborn while balancing on the top-tube.

It's actually very difficult to peddle like that if you've got long legs like me...I tried it (sans newborn).

Back on topic...

Not sure if anything here will work, but it's worth a check: Pac-Audio.com.

Also, check Coastaltech for their lockpick device.

Yeah, I ran into the Lockpick C8 reading various Dodge/Chrysler enthusiast forums, and that would be the ticket for getting a nice aux input that I don't have to pump through the headphone jack on the front of the factory unit (among other nice things it adds.) It'd be absolutely perfect if one of the things it gave you was an audio *output* for the factory system -- then I could just pump that into my empeg's aux input, set up the cellphone mute == switch to aux behavior, and I'd probably be in good shape.

Of course, this whole exercise has hit a bit of a snag, as the upcoming model year changeover at the factory means dealers aren't taking new orders for 2012s now, and no dealers within 300 or so miles have the car with the color/options I want. Hopefully the 2013s don't have an even worse situation going on with the factory system...

would one of these get you the audio output that you need?

You know... that just might work (though it looks like there's a slightly different model number for the 2012 Dodge vehicles.) I'll have to check to make sure it works with the specific radio model that I end up with, but that does look promising. Thanks!

Also might want to check to see if it can be daisy chained with the Lockpick (or does that use a different connector?).

Glad to help. Kills the time while sitting around the hospital.

I have the new car now. There's really nowhere I could put the display extender face that wouldn't look terrible or be hard to reach, so I think at this point my only hope is a "headless" sort of install where I stash the empeg in the glove box, use my cell phone as a display for it, and use.... something to control it, either the cell phone or steering wheel controls.

The problem is I can't find anything that integrates the steering wheel controls for 2012 Chrysler vehicles, and even if I do, I also need them to work with the factory system, so it would have to vary what the controls do based on which input is selected on the stock head unit or the empeg (depending on which is the head unit and which is the aux) and I don't see that as a likely outcome.

There's always the possibility of some sort of IR steering wheel remote like I had in my old car, along with an IR repeater that runs into the glove box, but that's really hackish and requires me to fiddle with two sets of steering wheel controls. I also don't like the idea of having to use a smallish cell phone screen to control the empeg.

I'm going to ask my local stereo installer if they have any ideas, but right now my thought is if I can't get the steering wheel controls to work with the empeg and the factory system, I'm probably going to be sans-empeg in this car.

Bah.

I copied some of my MP3s onto an SD card and popped it into my factory system, expecting some tag problems, maybe some missing cover art... Turns out it can't read the ID3 tags at all. They're ID3v2 2.4 tags that everything else can read, but I guess the Chrysler UConnect software can't deal with them. So I get to spend my Sunday afternoon screwing with different tagging programs trying to get tags that the system can deal with.

Looks like I'll be working a bit harder to try to shoehorn the empeg in somehow.

Good lord. Not only is the ID3 reading broken, but it seems to start playing each track 2-3 seconds in, completely skipping the beginning of every song. How does something like this end up making it to consumers?

No one along the line really cared, and consumer feedback hasn't been strong enough to force a change would be my guess.

Ford recently sent out USB thumb drives to all of their customers with a newer Sync enabled car with an upgrade on it. They did this because their overall car satisfaction ratings were taking a hit due to how bad the new system was. They wanted to get the changes out quickly instead of having people do it manually, or waiting till their next service appointment.

In car entertainment is still an area that could use a lot of improvement. We here all were spoiled with such a great product in 1999. My experience with the CarPC showed me that even the enthusiast market isn't really in it to make something great.

The cubby in front of the gear lever looks promising, maybe the lighter socket can be relocated to inside the armrest? How wide is that hole?

Yeah, that sounds about right. I'm actually finding that it does start some MP3s at the beginning, but others start late. Looks like it might be an issue with encoding of some of my older MP3s, though they play fine on my Squeezebox and in Google Music.



That would be a bit low to be able to easily view the display, but it would be something. I took apart the dash last night and it looked like it could fit, but it'd probably have to be at an angle.

But then I did some more googling this morning, and found this:


It replaces the factory climate controls and nixes the volume/tuner knobs so that a DIN unit can fit in. I'm pretty sure this means I'd lose the SD and CD/DVD drives, but maybe with the help of a display extender, I could come up with something where the disembodied empeg display tilts up to reveal those slots underneath.

Only problem is, I can't tell if the silver fascia area needs to be cut to fit that unit in. Checking with a local installer to see what the deal is -- there doesn't look like a lot of space between the video screen cutout and the climate controls, which makes me think this might require more dash cutting than I was hoping for.

Some clarity from the support staff at Metra: that kit is for factory systems with a smaller touchscreen. So I guess the cubbyhole under the climate controls is my only option.

That is exactly where Im now looking to stash my Empeg in my 2010 Santa Fe. Same basic spot. Going to tear into it this weekend and see. Oh, and the factory unit in that has the same set of issues yours does - doesnt deal well with some MP3s, tags are sometimes used and sometimes file names. what a POS. I want to look more closely into the SERIAL display extender that V99 talked about on here a few years back. That could be built in a smaller size than stock too, and fit more places.

Since discovering this project, my install plans have gotten a bit simpler, but also a lot more complicated. Simpler in the sense that I might not have to worry about finding a physical location for the empeg display panel, but more complicated in that it involves adding some more components, doing some hardware hacking, and a lot of additional software bits.

Attached is a rough picture of what I'm considering doing:


My first cut is going to be with the empeg as an aux-in device using the Lockpick C8 to add an auxiliary video input. The empeg display buffer will be sent to a RaspberryPi as per the project linked above, with the RPi pushing the empeg display (possibly along with some other stuff) to the aux video input on the Lockpick.

For empeg input, I'm looking at hacking together a custom switch panel that will be placed in the cubbyhole underneath the climate controls. The input will be read by an Arduino board with a CAN bus shield, which will also monitor the CAN bus for relevant activities in the factory A/V system (so it pauses the empeg when switching to another input, responds to steering wheel remote presses for next/previous track, etc.)

(I looked into trying to do all of the input and CAN stuff on the RPi so there are fewer moving parts, but CAN support on the RPi seems to be somewhere between totally absent and experimental at this point, whereas the Arduino CAN shield purports to be pretty much plug-and-play with a pretty robust set of library calls and some easy-to-follow example code.)

Of course, with such an ambitious project, there's many a slip 'twixt the cup and the lip, so I'll probably do everything in stages, starting with getting the Lockpick installed and feeding in the empeg as an aux device. If I hit any dead ends, I can always try to go the "conventional" display extender route instead.

I'll post updates here when/if I make any progress on any of this.

I admire your determination and will enjoy watching your progress.

EDIT: Personal preference, but I would ditch the button panel and just use an empeg remote with an IR extender and the steering wheel buttons. Much cleaner. If you REALLY need to get to the buttons on the empeg, you could always pull over and get in the glove box.

In my Blazer, my empeg was installed in a low position that was hard to reach, and I used my remote all the time. I got very good at using it by feel alone without taking my eyes off the road.

This CAN interface is supposed to be verified to work with Raspberry Pi: PEAK-System.

Disclaimer: saw the link while browsing for something else. Didn't read it.

EDIT: Holy Outrageous Price, Batman!

I do suppose the IR extender route would be less work, but I always found navigating menus with the remote to be more awkward than using the front panel with its D-pad-esque button arrangement. I also tend to drop or lose the remote in my car. I could always mount it semi-permanently, but I think I'm going to at least play around with the input panel idea, even if it just turns out to be an educational project rather than anything practical.

Yeah, the other good thing about the Arduino CAN board that I didn't mention is that it's pretty cheap. I did run into that PCAN-USB module on the RPi forums, and once I saw how much it cost, I realized Arduino was the ticket for now.

...Velcro

I'm on the "remote love's team"

Love to press #2 to pop in another song from the playing artist.

Yeah, I did say "I could always mount it semi-permanently."



Right, hence my motivation for a keypad on the input panel. I can't live without the ability to do order tweaking or keypad searches. As a matter of fact, those two features might make up a majority of my motivation for doing this rather expensive and time-consuming project.

Anyone know how difficult it would be to carve up a spare Kenwood KCA-R6A credit card remote to serve as a hard-wired keypad? I don't know anything about the internals of the remote, but I'm wondering if I could just connect to a few contacts inside and be able to process the key presses without dealing with powering it or interpreting the infrared signal. It's just a matrix of microswitches like any other keypad, right?

There's gotta be an easier way. What would be the advantage of that over something like this?

The screen-printed buttons that match the actual functions, mainly. I already ordered a 12-button keypad I can use, but I wanted it to look half decent, not just like a telephone keypad that happens to control an empeg.

Just a little bit of progress to report so far.

I received my Arduino kit and some controls the other day, and put together a quick mock-up of the code to handle the control input and send it over the serial interface to the empeg. I've got the knob left/right/press and the keypad input working with some cheap controls that I won't be using in the final input panel (if I get that far.)

Thinking about it more, I'm coming around to the notion that hard-wiring a Kenwood/RioCar remote will probably look lame, so I'm going to give that mini keypad a shot. I will still need to find some buttons small enough for it, or some sort of plastic membrane style thing to put over the switches, but assuming I can figure that out, that'll probably be a nicer looking install. Another option is to do my own matrix of square pushbuttons, which opens the possibility of using LED-illuminated buttons, but the ones I've found on Digikey and Mouser are all pretty pricey.

With all of the inputs, I'm out of pins on the Arduino, so I'll have to do some muxing. It looks like this guy is a cheap and easy way to get as many as I'll need.

For the input panel itself, I found a reference to this site in an old thread here, and it looks like getting a panel in anodized aluminum will run me somewhere in the $30-$40 range depending on how many drill holes/cutouts there are. Seems reasonable, but it's the kind of thing I'll really need to get right the first time, as they won't do proofs for a one-off project. I'll probably just be using wood and epoxy on the back of the input panel to mount the controls in, as a full enclosure would just end up being bulkier and would be hidden from view anyway.

The CAN bus Arduino shield should be here early next week, and I look forward to playing with that to see how much control I can get over the factory system and Lockpick, which should also be here next week. I also ordered one of those quickconnect harness jobs so I don't have to hack up the factory or Lockpick harnesses.

Search for "I/O Expander" chips on digikey. These connect over SPI (best) or I2C (fine, but slower) and add another 8 or 16 GPIO ports per chip you add.

Cheers

.. or just add more Arduino chips. The bare chips cost under $4/each, are easily programmed with the Arduino bootloader via a parallel port cable or another Arduino, and don't need much external circuitry.

What's the benefit of those options over the 74xx165 solution?

Cheap, less bulky, and bi-directional. The board you linked to says it is input-only, not output.

Cheers

Also note that if it's mainly push-buttons that are chewing up your I/O pins, there are a few easy ways to mitigate that.

(1) Arrange them (electrically) in a grid, like a keypad. Then you only need enough pins for x-y coordinates. Eg. 8 pins instead of 16 for a 16-button array.

(2) Use resistors, assigning a different resistance value to each of several buttons, and then wire them all to a single analog input on the Arduino. The exact button pressed can be determined from the value returned by the analogRead() function.

The empeg/Kenwood steering wheel remote uses strategy (2).

Cheers

OK, cool. I had seen some Arduino library code for the MCP23008 IO expander, but the shift register solution seemed simpler. Can you daisy-chain these IO expanders the way you can with the shift register boards?

EDIT: Looks like the I2C version can handle multiple chips on the same bus, but the SPI version can't.

EDIT 2: I didn't see your second reply when I posted mine... I'll look into those strategies as well.

SPI is fine with multiple devices per bus, but does suffer from the need to dedicate an I/O pin per device for "device select".

I2C of course has device "address" as part of the protocol, so there it's just a matter of how many different device addresses any particular type of chip can do.

But either way, a pair of 16-bit expanders give a LOT of extra I/O. But if one really needs tons of I/O, then perhaps the solution is to start with a larger microcontroller. There are Arduino boards with bigger chips ("Mega 2560" board), and then there's the Wiring-S board (very, very similar to Arduino), both of which offer 54 I/O pins.

Cheers

Note that there are tons of MUCH cheaper "Arduino" boards and accessory boards on eBay, if you can wait a month to receive them from China.

Typically 1/3 the cost of the "Arduino" branded ones.

A bit more forward progress. I got the CAN bus shield working, and though the libraries sample code are a bit lacking, I was able to do the basic "detect RPMs, accelerator pedal position, etc." thing over the OBD-II CAN bus connection. I'm probably going to have to do some proper library routines to make things manageable as I add more stuff, but it all seems doable.

I also received and installed the Lockpick last night. I'm hoping that it responds to CAN commands so I can make the task of switching inputs easier -- right now the only way to switch to its AUX A/V input (where the empeg display and sound will be going) is to hit the "Back" steering wheel button 4 times, then select the input from a menu. There's enough lag that this would be a real hassle. I was also hoping to be able to rig things so it switches away from the empeg input when calls come in, and without a dedicated CAN message I can send to the Lockpick, that's going to be difficult or impossible. If I can't find any dedicated commands, I'll have to settle for sending steering wheel presses. The Lockpick itself does some CAN mangling, so I'm thinking about monitoring the messages going into and out of it to see what it's doing for some ideas.

I have a Raspberry Pi arriving tomorrow, so I'll probably start playing around with that next. I'll need to check in with John to see if his code for writing to the RPi frame buffer is in good shape. Once I know how the RPi is going to fit in, the actual empeg install is next -- there's not enough room in my glove box for a sled, so I'm going to have to go the sledless route with Hijack's force car mode and/or force DC functions. For the time being, this rules out using the empeg as a head unit, but I think there are too many missing pieces for that now, anyway. Maybe some day.

Sorry to hijack, but where'd you get your RPi from? I need to order one and have it delivered by the 15th, but am reticent to pay $60 on Amazon when I could possibly get it much cheaper.

I ordered from Newark / element14, which is one of the two resellers linked from the RPi homepage. It was back-ordered for a few days, but it shipped out on Monday.

Last night I got the RPi up and running, built a toolchain, and did a quick "hello world" test of the cross-compiler. The frame buffer interface in Raspbian seems pretty standard, so I shouldn't have any problem driving it, though making it fast might take a couple of iterations.

One unexpected snag: it appears the RPi GPIO pins are 3.3V, while the pins on the Arduino are 5V. There are some ways to work around this, but it does give me more motivation to find a way to factor the Arduino out of the architecture and do everything I can on the RPi

The other option would be something like this, which is a stackable Arduino that's basically plug-and-play with the RPi. It's only in beta, but if they're close to production, that might be the simplest way to get things going until CAN on the RPI is farther along.

Sparkfun has 3.3V Arduino boards -- nice and tiny ones like the "Pro Mini" and "Pro Micro".

Cheers

Right, but I don't think they'd be compatible with the CAN bus shield I'm going to be using. Plus, I rather like the idea of powering the Arduino board off of the RPi, and having the boards stacked together for a cleaner install. Unless those "a la mode" boards are really expensive or end up getting delayed by months, I think I'll at least give it a shot, as it seems to fit the exact requirements I have for this project.

Sounds like end of October and $45 for the alamode board. A bit more spendy than I was hoping.

This weekend's big accomplishments were running the accessory power, ground, and CAN wires into my glove box, and hacking up a quick Raspberry PI empeg display program based off of Jon's excellent work on his massive LED display.

Right now I just have it showing the empeg display on the TV in my living room while I work on what the rest of the interface will look like. With all the screen real estate left over due to the empeg's very wide aspect ratio, I was going to display track data and cover art from the current song, perhaps along with some sort of "now and next" display if there's room.

I haven't had time to do the CAN bus analysis yet, but now that the CAN wires are in the glove box it should be a lot easier since I won't have to tear apart the dash. Getting all the wires and the Lockpick unit to fit in there is hard enough that I'm hoping I never have to open it up again.

Awesome, sounds like it will be incredible when you're done.

Any progress?

A little bit, but nothing else in the car. I've been focusing my time on getting the software bits together for the remote display stuff. Here's a short video of what it looks like so far.



Still plenty of work to be done making it look pretty and reducing delay in loading new tracks, etc. but it'd certainly usable at this point if I had the input stuff working (I guess I could go the IR extender route with it as-is, but what's the fun in that?)

Damn impressive. Someday I'm going to have a car with one of those kinds of screen-y nav-y thingys, and I'm going to need a solution like that. I think your solution is looking extremely promising, and when that day comes, I'm going to ask you for all the software and the hardware details so that I can build one myself. :-)

Yeah, it's mostly ideas stolen from Jon's RPi LED thing and old bits of emphatic code that I've repurposed. The CAN bus hacking part is going to be the big time sink, so I've been focusing on stuff I should be able to use whether or not I can make that work properly.

There are some issues -- you can see in the above video that the running length order starts out wrong and corrects itself, which is because the dynamic data partition takes a while to get updated when you select a new playlist or add tracks to an existing running order. I don't really have a solution for this, so getting now and next display to be 100% accurate might be out of reach, but I'll take what I can get at this point.

Are you saying the display shown doesn't match the front panel display on the empeg itself? Why not? Hijack provides a perfect snap of the current display in both raw and .png format, updated whenever it's read by any app. Use that!

Cheers

Looks like that's his top half (mirrored via hijack) and the bottom half he's creating himself based on the dynamic data?

?

Yea, I'm grabbing the player screenbuf for the top half and generating the bottom half. What I'm saying is that in order to get the running order length as a number (not as pixels) I need to read the first sector of /dev/hda3, which some time takes minutes to update. This is why you see [1/6] on the top and [1/40] on the bottom, since the previous running order had 40 entries.

It's been another month. Any progress on this? (Not trying to be pushy...I just find it an interesting project.)

Not as much progress as I'd hoped. The RPi and empeg apps are fine -- I added album art display, configurable track data, etc. and it would be usable as-is if I could get the freaking CAN stuff to work. I can read CAN data on the OBD-II connector, but for some reason I can't get anything from the CAN-B (convenience) bus that connects to the radio. It's probably something stupid where I messed up a connection somewhere, but I've tried a bunch of different stuff, and since nothing's documented, it's hard to tell the "baud rate isn't what I think it is" problem from the "wires aren't connected" problem, since the CAN chip initializes successfully either way. I spent about an hour on it tonight and got frustrated, but am hoping to take a look again tomorrow to triple-check connectivity, maybe try something different with the Arduino code, etc.

If I can't figure it out, I'm probably just going to punt and order an IR extender so I can have something usable in the car. The major drawback to that (other than the fact that I'll need to reach for the remote all the time) is going to be that it takes six or seven button presses to switch back and forth from the Lockpick's A/V input to the factory stereo (something I was hoping to automate with the CAN stuff.)

Logic-analyzer time.

Yeah, I should really get one of those. Any suggestions for one that will do the job but won't break the bank?

Well, you can make a simple one using an arduino chip. Very cheap, but takes more time.

Then there's the Logic Analyser thread here.

Maybe something like
http://dangerousprototypes.com/2010/04/22/bus-pirate-can-pirate/

Not entirely sure where you think the problem may lie though.

edit: you may need something more like an oscilloscope if you're not sure about connections.

I'm sure about the connections, for certain values of "sure."

I used a multimeter to quadruple-check that the pin numbers are identical for my OBD-II-to-DB9 cable I'm using for the main CAN bus (the one that works) as they are for my custom radio harness to DB9 cable that I'm using for the CAN-B bus (the on that doesn't.)

The "good" news is that I'm getting at least some radio-related output on the "main" CAN bus. I haven't decoded it yet, but I definitely get unique message when changing inputs, presets, etc. I was led to believe all the radio-related stuff was on CAN-B, but that doesn't seem to be the case.

Figuring out how I can *initiate* these might be tougher, though I did get some code from someone who did it with an older Chrysler radio that I'll probably try tonight.

For now I'm going to work with the bus I can read, and if I can't make any progress, I guess I'll have to buy a scope or logic analyzer.

That sounds like your custom radio harness isn't right if anything or somehow it's a different CAN.

Maybe CANH and CANL are the wrong way around? Perhaps with a multimeter it might show enough similarities or differences that you have things right or wrong. My limited understanding of CAN is that idle should go to something like +5 on H and 0V on L.

I'm getting 5.66V or so on both of them, so maybe I don't have the right connections.

I can't find a good reference for the pinouts on the 2012 Charger since it's a relatively new vehicle, but the physical shape of the plug and the number of pins matches this guy, and this PDF does list the pinouts, with pin 2 labeled "CAN BUS (+)" (which I've connected to the CAN-H input) and pin 13 labeled "CAN BUS (-)" (connected to CAN-L.)

Well if they are basically the same and the same polarity you probably have the right way but standard CAN should be 0-5V. So that's a little strange but at least consistent between the two buses.

If you're getting something on the general bus, how is that possible *without* the CAN-B bus working? There must be stuff going across those pins 2 and 13 with some kind of gateway between the two. Maybe monitor those pins whilst there is traffic like steering wheel button presses. Even with a multimeter you should see some small change.

One new data point tonight: the multimeter shows 2.5ish volts on the CAN pins on the known good cable connected to the OBD connector, which suggests that the pin numbers listed on that PDF are incorrect. I can't find anything more authoritative for the 2012 model year, and I'm not really sanguine on the prospects for poking around with the multimeter trying to find the the wires that way, so for now, I'm going to go with plan B and find an in-car IR extender just to get something working. I'll keep my eyes peeled for some sort of official documentation on where to get the CAN-B connections, and see if I can find anything on the main CAN bus.

You write as if A and B are physically separate busses. Is that really the case? Or are you just talking about the differences in the connectors?

There are three separate CAN buses in these vehicles, as shown here and described here. The diagram is a few years old, but I'm told it should still apply to the 2012s. The "FCM (CGW)" box is apparently some sort of gateway that would let me get through to the CAN-B bus from the CAN-C diagnostic bus, and someone on the canhack.org forums claims to have done so, but hasn't described it in detail, so I'll believe it when I see it.

A kind soul on the canhack.org forums pointed me in the right direction for the pin-outs. This site has connector diagrams and pin numbers for almost any connector in any Chrysler vehicle. The right answer, found here, is pin #s 7 and 18.

Now my new problem is I've got a flaky speaker connection that seems to have come loose while I've been screwing around with all of this. I thought I'd fixed it last night, but it went out again while driving today. I'm hoping I can fix it permanently without professional assistance.

"professional" merely means "paying somebody else to do it". It does not guarantee that the person paid is any better or more knowledgeable than you.

In the case of a flakey wire, I suspect you know as much as anyone about it, given that you've been crawling around in there recently.

Cheers

Thanks for posting that site. With two Jeeps and a Magnum I may be needing something like that someday.

(Partial) Success!

Pins 7 and 18 it is -- got a good CAN-B connection and am able to read the data. Now comes the really time-consuming part where I reverse-engineer what's happening on the bus.

I also got the flaky speaker situation sorted out. I was blaming a loose wire going into the back of the factory harness, but it was actually a pin in the connector that was bending out of the way when I connected my custom harness. Nudged the pin back into alignment and everything seems solid. *crosses fingers*

Whew. What a hassle. On the bright side, I've gotten really good at field-stripping my car's dash.

Much better! Well done!

/me cheers from the sidelines