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Discussion Starter · #1 ·
OnStar does not provide services in Europe. This means that there is no possibility to enable additional services like remote starting the car with iPhone, locking/unlocking the doors or checking up the battery levels. This brings up the question that can these features be enabled somehow utilizing some other scheme?

For example how does the Volt communicate with OnStar in US? Does it have a SIM card slot where one could hook up a local phone contract? Does it only communicate with pre-determined "service" number to OnStar (which would mean that international SMS charge would apply)? Could this be changed so that one could use phone to send SMS to the car? Is there app for iPhone to do just this?

Dealer/Chevy Finland comment was just "No OnStar services are available".
 

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I'm surprised OnStar would leave that market unserviced.
...best bet is
http://www.openvehicles.com/
...its hardware uses a sim and android for communications
Their system is pretty Tesla Roadster-specific. The problem with even their new hardware is that its basically stuck with the OBDII standard commands, so you can get some information, but most of what OnStar does goes across the 33k single-wire CAN bus in the Volt. Its exposed on the OBDII connector, but I have never seen a CAN-bus adapter that works out-of-the-box with the SWCAN bus in the Volt. You can tweak and adapt interface hardware to be able to access the bus, and then everything OnStar can do to the car you can do as well.

There was a guy who was selling, briefly, a couple years ago a Bluetooth CAN adapter that was tweaked to talk to the GM SWCAN bus, but he "disappeared" a while back and I've never found anyone else making something.

I've been slowly adapting my Windows Phone app that OnStar shut down with plumbing that replaces OnStar entirely, but lacking an easy interface cable, there's not really a good way that people can DIY it who aren't fairly familiar with CAN electronics.

OnStar used to run on Verizon's analog network -- I don't know who they are using today when Verizon shut off their analog network, but I'd be willing to bet it is still Verizon 2G CDMA (based on signal strength I've seen on my ATT phone), so no SIM cards.

There's not much to OnStar, though -- its basically just a cellular voice system and data gateway to the vehicle's CAN bus, which is how they can offer the voice-based services, too. From what I've seen (and from what other people over the years have written up), GM didn't do anything stupid like cross-encrypt the data on the CAN bus, so any device on the bus can get the same reactions. (I haven't gotten that far, but I'd be willing to bet, from what I've see, that the CAN messages that the remote control receiver sends out to remote start the car is the exact same one the OnStar unit sends out, for example...) I've set up a similar setup for a custom car via Bluetooth. Tying it with a key exchange to services over GSM wouldn't be too hard. Its not quite the same as in my case the stuff I was communicating with was dual-wire CAN, which is easy to get interfaces for.

The real trick is getting a standard cable that can talk to that bus. Everything else isn't particularly complicated.
 

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Discussion Starter · #4 ·
OnStar used to run on Verizon's analog network -- I don't know who they are using today when Verizon shut off their analog network, but I'd be willing to bet it is still Verizon 2G CDMA (based on signal strength I've seen on my ATT phone), so no SIM cards.
So that would pretty much mean no service in Finland as we don't have CDMA network at all. GM would need to redo the car electronics for enabling the finnish (and most european) networks. Also homegrown system would need separate device to be installed. Seems to me something that would come out under Opel brand, maybe I'll check out some german Ampera sites for similar possibilities.

I do know that GM was talkn with Telefonica few years back for providing OnStar to european customers, but the information was rwally vague like "maybe in some years". Most likely vaporware like powermat for Volt.
 

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I am pretty sure the openvehicles group has an ampera solution working or in beta at this time.

check this thread

http://gm-volt.com/forum/showthread.php?12958-CAN-bus-reading-remote-viewing-of-charge-state
Those are still OBDII, not the SWCAN. I guess it depends what you want out of "OnStar" -- I rarely used, or cared, about the status information OnStar gave. It was the actions that were useful (remote start, send a destination, etc). Those messages are all on the SWCAN bus, not the OBDII bus.
 

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Hi, markwj here from the OVMS project.

We've made quite a bit of progress on the Volt/Ampera support. Overall, the project has definitely moved beyond Tesla Roadster, with Twizy support already fully up and stable, basic Volt/Ampera support working, and now trying to add support for Tazzari, Think City and some others. Our v2 firmware was re-worked to be vehicle-agnostic, and the vehicle firmware modules are now implemented as plug-in code modules selectable at run-time.

The OVMS module is pure CAN (up to 1Mhz, with hardware filters) - dual wire CAN by default. For Volt/Ampera at the moment we're using a mix of pure CAN listening and OBDII extended PID requests directly over the CAN bus.

Interested in the discussion here regarding SWCAN. We have been looking for those remote-start style instructions, but haven't seen anything documented or anyone else discussing them.

It appears that interfacing to SWCAN, given a 2-wire CAN controller, is not too difficult. This guy:
http://gtosoft.blogspot.hk/2011/06/how-to-make-swcan-adapter.html
has something, and the datasheet for the 8056 SWCAN transceiver seems quite straightforward. As we have +12V power, GND, and 2 wire CAN on the OVMS module connector, as well as SWCAN on the OBDII car connector, this could probably be done as part of the cable to the car, without any change to the module necessary. But, I guess that SWCAN does not contain any of the other stuff we are looking for (like battery SOC, charge status, etc)?

Do you have any information on the SWCAN messages for these remote start, door lock/unlock style commands? Anything published or willing to share?

We've just recently started looking on the standard vehicle CAN bus for these remote start commands. It is very early days, but we've identified some OBDII style extended PID requests/responses as well as 0x1A style 'read extended diagnostics ID' commands that appear to wake up the car.

Regards, Mark.
 

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Hi, markwj here from the OVMS project.

We've made quite a bit of progress on the Volt/Ampera support. Overall, the project has definitely moved beyond Tesla Roadster, with Twizy support already fully up and stable, basic Volt/Ampera support working, and now trying to add support for Tazzari, Think City and some others. Our v2 firmware was re-worked to be vehicle-agnostic, and the vehicle firmware modules are now implemented as plug-in code modules selectable at run-time.

The OVMS module is pure CAN (up to 1Mhz, with hardware filters) - dual wire CAN by default. For Volt/Ampera at the moment we're using a mix of pure CAN listening and OBDII extended PID requests directly over the CAN bus.

Interested in the discussion here regarding SWCAN. We have been looking for those remote-start style instructions, but haven't seen anything documented or anyone else discussing them.

It appears that interfacing to SWCAN, given a 2-wire CAN controller, is not too difficult. This guy:
http://gtosoft.blogspot.hk/2011/06/how-to-make-swcan-adapter.html
has something, and the datasheet for the 8056 SWCAN transceiver seems quite straightforward. As we have +12V power, GND, and 2 wire CAN on the OVMS module connector, as well as SWCAN on the OBDII car connector, this could probably be done as part of the cable to the car, without any change to the module necessary. But, I guess that SWCAN does not contain any of the other stuff we are looking for (like battery SOC, charge status, etc)?

Do you have any information on the SWCAN messages for these remote start, door lock/unlock style commands? Anything published or willing to share?

We've just recently started looking on the standard vehicle CAN bus for these remote start commands. It is very early days, but we've identified some OBDII style extended PID requests/responses as well as 0x1A style 'read extended diagnostics ID' commands that appear to wake up the car.

Regards, Mark.
Hi Mark,

There's a few "hacky" ways to adapt dual wire CAN adapters. Its unfortunate that GTOsoft disappeared -- the adapted Bluetooth CAN adapters they'd been prototyping would've been perfect for what I was doing. I've got a hacked up serial CAN adapter I've been experimenting with.

I can see the commands being sent as the car is doing things like remote starting. I *think* I am seeing navigation information on it when OnStar sends it, so I believe the radio is also coupled into the SWCAN bus. I've seen reports online that most GM cars do windows via the SWCAN bus, as well.

I've mostly been focused on a) confirming I can see some data and b) confirming I can get a reasonable CAN adapter before I went too far into the protocol reverse engineering. I've seen no reports that GM encrypts anything on the SWCAN bus, so that's mostly easy "busy" work and hasn't been my focus yet.

Right now the biggest blocker I'm seeing is that none of the "hacky" adapted CAN adapters can do the dual voltage signals onto the CAN bus, and the modules on the bus need the 12v signals to "wake up" if the car has been off for any period of time. That's a show-stopper in terms of replicating what OnStar is doing.

If I had a reliable cable that could send and receive onto the SWCAN bus, including the "wake up" signals, the rest would come pretty quickly. (My focus is on really two things -- remote start, and getting nav directions to the radio, which are the only things I ever used OnStar for, although I'd also like to catch logs as the car was sending alerts to the dash for things like "ice possible", as I'm pretty sure they probably go over SWCAN, too.)

In terms of what is on which bus, easiest way to find out would be to pull the OnStar unit and see which busses it has access to. I'm betting it does not have access to the high-speed bus, so I'd bet the other data you want (battery status, etc) is either on the "normal" OBDII bus, or the SWCAN.
 

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When you do a remote start via the key fob, which bus are those messages on?
(freakin' A, I wish this damn website didn't have "reply to thread" and "post quick reply" on the screen at the same time -- lost my reply twice so far...)

I've seen data transmitted during the remote start I suspect contains it. It makes sense -- in other GM cars, the SWCAN bus contains most, if not all, of the commands between the unit that handles the fob and the vehicle, the radio, the dash, windows, etc.

I never bothered to narrow it down until I knew I'd found a good interface solution, which I haven't yet.
 

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There's a few "hacky" ways to adapt dual wire CAN adapters.
From what I can see, the 8056 is designed specifically to interface 2-wire can transceivers to SWCAN. The datasheet is here:

http://www.melexis.com/Asset/TH8056-DataSheet-DownloadLink-4810.aspx

The CAN controller RX+TX should be able to go straight to it. It would take some soider-hacking to get it working with OVMS. Interestingly, the pinouts for the TH8056 KDC A8 variant are almost identical to the MCP2551 (standard 2-wire CAN controller). The only difference seems to be the MODE0, MODE1 pins. I'm wondering if this could just be dropped out and replaced, but would need to check the wiring diagrams to be sure.

As you say, though, I doubt whether the other stuff we want (SOC, range, etc) is on the SWCAN bus.

In terms of what is on which bus, easiest way to find out would be to pull the OnStar unit and see which busses it has access to. I'm betting it does not have access to the high-speed bus, so I'd bet the other data you want (battery status, etc) is either on the "normal" OBDII bus, or the SWCAN.
I suspect a lot of this is gatewayed onto the main bus.

For example, during an OnStar status check to an asleep car we're seeing this on the main bus:

10:44:47.323 R11 7E4 02 1A A5 00 00 00 00 00
==> Read diagnostic ID A5
10:44:47.335 R11 7EC 04 5A A5 01 03 AA AA AA
==> Respond diagnostic ID A5 is 0103

After that, the car is awake and the bus has the usual messages. As usual with CAN, we can't see the source, just the destination.

We're also seeing on the main bus:

ID=32A B1-B4 GPS Latitude in milliarcseconds
B5-B8 GOS Longitude in millarcseconds

But, those only appear valid on cars equipped with OnStar. On European cars they are transmitted but the values are all zeros. So, it appears that if the OnStar is not on the primary bus, at least some of its messages are gatewayed there.

We made some good progress with this last week, but the CAN logging tool the guy helping us was using is not fast enough - he's losing too much of the data at 1Mhz and the tool he has doesn't have hardware filters. He is getting a faster tool and then will resume logging and trying to isolate the messages (if they exist) on the main bus.
 
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