2008 GMLan radio bench testing?

[techknight]

I have a couple of the 2008 GMLan radios that I did some repairs on.

Does anyone happen to know the commands that enable the radio to turn on? I noticed the other thread where people are toying with the GMLAN CAN bus.

I could use an AT90CAN128 chip, or maybe even the CANbus arduino shield and hook directly to the 2 GMLAN connections in the back of the radio directly.

Any help would be appreciated.

[ZerOne]

A couple of us were trying to work this out a while a go, as we were playing around with things, and having the device on the bench just made everything so much simpler.

Unfortunately with the Series I stuff, just the sheer number of commands that are sent on the SW Bus when the Bus wakes up was flooding the Can sniffing devices we had at the time.

In the end, I don't think anyone worked it out. (It just became simpler to plug the radio in to the car for testing).
I even got to the point of wiring up a BCM, radio and cluster together to see what I could get happening on the bench, and the result was fairly predictable.... Nothing....

Luckily series II (Holden IQ) models can be powered up on the bench without any SW Can connection, but unfortunately that doesn't help with your situation.

[techknight]

Yea, I have no idea what series this is. I just know that it has a dot matrix VFD display tube. the VFD driver was burned out and I had to replace it.

[radrace19]

I ended pulling my BCM from the car to get the radio to work on the bench. I now have a spare radio and matching BCM.
Using a 2009 G8 radio and BCM are all that are required to power the radio and get it to function.
-Greg

[tmk]

My guess is you would need to send a high voltage wake up command to wake the radio and then a keep alive and intermittant VIN number packets.

Never tried to do this but would love to dig into it some in the new year. I have a spare head unit and a single wire capable arduino..

Anybody have any ideas as to which CAN packets keep the infotainment alive?

TMK

[tmk]

http://www.canbushack.com/blog/index.php?title=network-management-part-1-gmlan&more=1&c=1&tb=1&pb=1 - Canbushack had something on this..

Actually - there is the ticket - that and the correctly formatted VIN packets (ARBID 12 and 13) and I bet the radio comes on.. Maybe..

TMK

[DEngineer]

Hello,

I new to the forums, but have been testing some GM systems lately. I got a GM radio working on the bench by sending the Ignition Status command about every 2-3 seconds. Either the 'Accessory' position or the 'On' position works.
0x10002000 - Data 09 01 86 36 (Accessory Position)
0x10002000 - Data 0A 01 86 36 (On Position)

It does want to see the high voltage wakeup with 0x100, but you can forgo that by powering up the unit and start sending the Ignition Status before the CAN controller goes back to sleep.

It didn't seem to need the Virtual Network wakeup (0x621), unless you want it to interact with another unit, like the BCM.

I bought the radio unlocked (no VIN programmed), which initially caused some issues. Just hooking it up to the BCM allowed it to automatically program itself with a VIN, then it was happy. After the VIN was programmed, it didn't need the BCM any more. It will only go to the lockout mode if a DIFFERENT VIN is detected.

I hope you find that helpful!
D

[tek1229]

Just to verify and update a little..

I was able to get a gmlan radio to turn on and operate on the bench with some very simple work..

A bluetooth elm327 OBD2 device and a program called Termite, any terminal emulation program than can do serial communication should work..

I connected pin 6 of the ELM to the gmlan pin of the radio pin 13 of C1..
I connected pin 14 to ground,along with the radio ground
I connected battery power to the ELM and to the radio but I added a switch inline to the radio..
4 wires and that's it.. I did have a problem when I started with data corruption until I researched it a little bit more and added a 120 ohm resistor across the gmlan pin 13 and ground..

you'll need to use these commands only once.. see the ELM327 instructions for explanation or ask if confusing..
AT PP 2C SV 60
AT PP 2D SV 0F
ATPP 2C ON
ATPP 2D ON
ATZ
ATSPB

Then once you have the ELM set up for GM lan communication sending 29 bit headers you'll need to do the following..
connect the battery to the radio, or in my case I was able to simply push the little 'i' button on the top left of the radio faceplate to 'wake' the radio up.. then..

you'll need to send 10 00 20 40 0A 01 04 44 which is ign on signal from the BCM.. I seem to need to do this every 5 seconds, with Termite this is pretty easy setting up the function keys and using the repeat function..
the commands below are how to set up the ELM
ATCP 10
ATSH 00 20 40
then simply type in 0A 01 04 44... with or without the spaces, caps or lowercase..

I know this is a lot of the same info posted above me already but I wanted to add the ELM327 settings and info..

[tek1229]

Pretty much used the above info to build a poor mans video in motion and NAV address entry in motion bypass.. Any interest in that here?? I've verified it's all working but I need to put the package all together.. time is hard to find nowadays that spring is here, lol.. This is more of a winter cooped up project.. Looks like I can make the rear camera turn on as needed too, not sure how much I'll want that when I'm not in reverse though... I haven't seen any writeups here like this, if this is too simple, or below the scope of this site, let me know.. Or I can write up what I've found out and how I go about it.. Kind of lengthy and probably not a very savvy way of doing it, heh heh but it works..

On a side note, I found this site using google to research a video in motion hack for my own personal vehicle, I had got my hands on a factory nav unit, worked out the missing vss wire, added an amp(Since I did not have a bose system), and then the audio wiring from the VCIM to the nav.. Was woefully disappointed when i found out I couldn't even let my passenger add an address to the nav while I was driving.. Started searching from there for a workaround.. I do have my own MDI and Tech2, I also have access to TIS,SI, etc.. I'll try not to ask for all the secrets, lol..Now onto a few questions if anyone knowledgeable here has the time..

As far as the VIM rewrite hack I have seen here mentioned, that is to change the speed at which the screen is locked out, correct?? On my vehicle(2013 silverado with an 08 nav unit) my screen locks out as soon as I shift it out of park, is this a different situation that what you guys here are working with?? Is this anything even remotely possible with limited knowledge and hardware I have available? Tech2? MDI? an Arduino with an elm327 modified for SW GMLAN access.. If I was to spend the time finding out how to do this(not gonna ask for location or specifics, I like the idea of a challenge) I think I would still be stuck with with being locked out unless I keep on interrupting the trans range status and faking the park status message.. if I am still stuck doing that, the way I fix the vss currently although not as smooth as a nice rewrite would be just too easy not to keep using.. Is there a rewrite trick for the range selection as well?? Maybe I could spend time trying to do both?

Thanks for any tips or suggestions... Tom