Enabling mixed frame and or extended Low Speed CAN single wire frames like those posted on GMLAN bible

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04colyZQ8
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Enabling mixed frame and or extended Low Speed CAN single wire frames like those posted on GMLAN bible

Post by 04colyZQ8 »

I am only getting 11 bit headers not 29 bit, how to fix this in universal patcher master?

I need something like this, I suspect the Onstar is sending these message frames 4 byte header? 29 bit I think
Ignition Key State ARBID 0x001, length 4 bytes
10002040 00 00 74 77 Key Out
10002040 00 01 74 77 Key In
10002040 09 01 74 77 Key Acc
10002040 0A 01 74 77 Key Run
10002040 0B 01 74 77 Key Crank
10002040 08 01 74 77 Key Off
10002040 08 00 74 77 Key Out (08 = Driver still present? or maybe just a time delay)
10002040 00 00 74 77 Timeout after approx 40 seconds with no key

But only get this
11 bit headers not extended frame

Code: Select all

[23:33:48.171] 00 00 06 2D 01 04 00 00 00 00 00 00 
[23:33:54.557] 00 00 01 00
[23:33:54.631] 00 00 06 2D 01 04 00 00 00 00 00 00
[23:33:54.666] 00 00 02 4C 03 22 C0 10 00 00 00 00
[23:33:59.918] 00 00 01 00
[23:33:59.972] 00 00 06 2D 01 04 00 00 00 00 00 00
[23:34:00.007] 00 00 02 4C 03 22 83 99 00 00 00 00
[23:34:05.248] 00 00 01 00
[23:34:05.278] 00 00 01 01 FD 02 10 04 00 00 00 00
[23:34:05.297] 00 00 06 2D 01 04 00 00 00 00 00 00
[23:34:10.540] 00 00 01 00
[23:34:10.552] 00 00 01 01 FD 02 10 04 00 00 00 00
[23:34:10.574] 00 00 06 2D 01 04 00 00 00 00 00 00
[23:34:15.856] 00 00 01 00
[23:34:15.879] 00 00 01 01 FD 02 10 04 00 00 00 00
[23:34:15.914] 00 00 06 2D 01 04 00 00 00 00 00 00
[23:34:21.205] 00 00 01 00
[23:34:21.208] 00 00 06 2D 01 04 00 00 00 00 00 00
[23:34:21.232] 00 00 02 47 03 A9 81 82 00 00 00 00
[23:34:26.486] 00 00 01 00
[23:34:26.489] 00 00 01 01 FD 02 10 04 00 00 00 00
[23:34:26.490] 00 00 06 2D 01 04 00 00 00 00 00 00




My other thread of the Onstar proving only low speed is needed.
viewtopic.php?p=134945#p134945
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Gatecrasher
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Re: Enabling mixed frame and or extended Low Speed CAN single wire frames like those posted on GMLAN bible

Post by Gatecrasher »

I don't know what needs to be done with UP, but that bus doesn't look healthy. There's diagnostic requests to the IPC and SDM with no response, a virtual network management frame, and constant bus wakeup commands.

If you're just testing a bare OnStar module it's not surprising that it's not entering normal operation until it can verify the rest of the car exists.
gmtech825
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Re: Enabling mixed frame and or extended Low Speed CAN single wire frames like those posted on GMLAN bible

Post by gmtech825 »

do you just need to log data? if so then use ironduke's console app to log pin 1. it's easy to use and works well.
04colyZQ8
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Re: Enabling mixed frame and or extended Low Speed CAN single wire frames like those posted on GMLAN bible

Post by 04colyZQ8 »

Gatecrasher wrote: Wed Aug 27, 2025 2:31 pm I don't know what needs to be done with UP, but that bus doesn't look healthy. There's diagnostic requests to the IPC and SDM with no response, a virtual network management frame, and constant bus wakeup commands.

If you're just testing a bare OnStar module it's not surprising that it's not entering normal operation until it can verify the rest of the car exists.
Yes bare module nothing else, but even when connected I never see 06 4D (onstar) messages yet the doors lock and unlock only if low speed is connected. I even have permanently disconnected high speed cab from onstar and it keeps working!

So onstar sends a magic message that I am not able to log? On low speed pin 1. Could have be on pin 1 with 83.33 k baud? Instead of 33.3k?

Do all GM vehicles have the long message on low speed
Can bus? The 29 bit header?
04colyZQ8
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Re: Enabling mixed frame and or extended Low Speed CAN single wire frames like those posted on GMLAN bible

Post by 04colyZQ8 »

gmtech825 wrote: Wed Aug 27, 2025 3:50 pm do you just need to log data? if so then use ironduke's console app to log pin 1. it's easy to use and works well.

Pretty sure I tried it but my mongoose cable wouldn’t connect.

The only example I see for extended frames is an adrino with can bus shield. Guess I’ll have to cobble up that. So frustrating trying to log low speed can bus.
gmtech825
Posts: 302
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Re: Enabling mixed frame and or extended Low Speed CAN single wire frames like those posted on GMLAN bible

Post by gmtech825 »

have you tried the drewtech logger with the mongoose?
ironduke
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Re: Enabling mixed frame and or extended Low Speed CAN single wire frames like those posted on GMLAN bible

Post by ironduke »

You can try this version of my logger. Option 11 connects with 2 different status flags, I seem to remember some tools not liking one of them.
CAN_ID_BOTH or NONE.

I've been trying to find some time at home to work on patcher and low speed ISO connections but just haven't had the time. This is just a quick mod that works on the bench with an RCDLR I happened to have pinned up. I'm not seeing any difference between CAN_ID_BOTH and NONE though.
I am getting 0FFFE0B0 from the RCDLR when I wake it up. If that's a 29 but header then it's just the header... No idea but maybe worth a try to see if your mongoose will work with a different status flag..
MDI Canbus Logger(3.24._0.5).7z
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04colyZQ8
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Re: Enabling mixed frame and or extended Low Speed CAN single wire frames like those posted on GMLAN bible

Post by 04colyZQ8 »

ironduke wrote: Wed Aug 27, 2025 7:38 pm You can try this version of my logger. Option 11 connects with 2 different status flags, I seem to remember some tools not liking one of them.
CAN_ID_BOTH or NONE.

I've been trying to find some time at home to work on patcher and low speed ISO connections but just haven't had the time. This is just a quick mod that works on the bench with an RCDLR I happened to have pinned up. I'm not seeing any difference between CAN_ID_BOTH and NONE though.
I am getting 0FFFE0B0 from the RCDLR when I wake it up. If that's a 29 but header then it's just the header... No idea but maybe worth a try to see if your mongoose will work with a different status flag..
MDI Canbus Logger(3.24._0.5).7z
J2534 Logger, works with MDI and MDI2 tested, others may work.
Option 7 debug is ONLY for when your saving to a file in case of lag to file, shouldn't be needed
When creating your own filters for CAN you need to add the 5 preceding zeros(000007E8,00000241,etc
1 - Log data for Engine ECU(7E0,7E8,7DF,101):
2 - Log data for Transmission ECU(7E2,7EA,7DF,101):
3 - Log data for Engine AND Transmission ECU(7E0,7E8,7E2,7EA,7DF,101):
4 - Log data for BCM ECU(241,641,541,7DF,101):
14 - Log data for BCM AND ECM ECU(241,641,541,7E0,7E8,7DF,101):
5 - Log data for with ID's you define, ex.000007E0/000007E2/00000101
6 - Log ALL data
7 - Debug enabled, data captured will scroll on screen when saving to file
8 - Exit
9 - Logging to file, Press 9 to show log on screen only
10 - Logging High speed(6&14), press 10 to change
11 - Currently CAN_ID_NONE for ConnectFlag, press 11 to change
9
J2534 Logger, works with MDI and MDI2 tested, others may work.
Option 7 debug is ONLY for when your saving to a file in case of lag to file, shouldn't be needed
When creating your own filters for CAN you need to add the 5 preceding zeros(000007E8,00000241,etc
1 - Log data for Engine ECU(7E0,7E8,7DF,101):
2 - Log data for Transmission ECU(7E2,7EA,7DF,101):
3 - Log data for Engine AND Transmission ECU(7E0,7E8,7E2,7EA,7DF,101):
4 - Log data for BCM ECU(241,641,541,7DF,101):
14 - Log data for BCM AND ECM ECU(241,641,541,7E0,7E8,7DF,101):
5 - Log data for with ID's you define, ex.000007E0/000007E2/00000101
6 - Log ALL data
7 - Debug enabled, data captured will scroll on screen when saving to file
8 - Exit
9 - No log file created, just show on screen. Press 9 to change
10 - Logging High speed(6&14), press 10 to change
11 - Currently CAN_ID_NONE for ConnectFlag, press 11 to change
1
1 - MDI
2 - MDI 2
3 - MongoosePro GM II

Input Device Number:3
Press the p key to pause log, all monitoring will pause
Press any key to stop logging
starting log in 1 second
Starting log


I have a e78 on the bench I checked its sending lots of data on HS can, yet nothing here.. I usually have a window open tech2win client, that selects tge mongoose pro. But not with this logger:)
04colyZQ8
Posts: 536
Joined: Thu Jan 16, 2014 2:41 am
cars: 2004 Colorado 4.8L swap
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Re: Enabling mixed frame and or extended Low Speed CAN single wire frames like those posted on GMLAN bible

Post by 04colyZQ8 »

awe.. log all works I assume it is high speed
[00:00:02.1987011] : 00000287C100000664
[00:00:02.1988773] : 000002C30664066A00000013
[00:00:02.1989870] : 000002D30305
[00:00:02.1991308] : 000003F9000000004F000000
[00:00:02.1992703] : 000003FB0000
[00:00:02.2023627] : 000003FC4400006E6E006E6E
[00:00:02.2077902] : 000000AA2A75326B064D9200
[00:00:02.2080116] : 000000BE0800000659FE
[00:00:02.2081908] : 000000C90000000A00111000
[00:00:02.2083574] : 0000018E43030066466B0664
[00:00:02.2085678] : 000001910664C664066B0000
[00:00:02.2088110] : 000001E70190000022D02D56
[00:00:02.2090698] : 000001ED0190000000002D56
[00:00:02.2202016] : 000000AA2A75326B004D9500
[00:00:02.2204622] : 000000BE0C00000659FD
[00:00:02.2208989] : 000000C90000000D00111000
[00:00:02.2210288] : 0000018E43030066466B0664
[00:00:02.2211517] : 000001910664C664066B0000
[00:00:02.2212669] : 000001A100104300B57000
[00:00:02.2214970] : 000001E70190000022D02D56
[00:00:02.2218356] : 000001A300
[00:00:02.2220321] : 000001ED0190000000002D56
[00:00:02.2221711] : 000001AA0066A66C66400000
[00:00:02.2222945] : 000001BA07797796A06647AF
[00:00:02.2225562] : 000001C34664066400000000
[00:00:02.2227359] : 000001C46D62C030070002FD
[00:00:02.2229743] : 000001C5326B326B3409
[00:00:02.2231755] : 000001DF000000
[00:00:02.2233368] : 000001F4000000000000
[00:00:02.2235541] : 000002870000000664
04colyZQ8
Posts: 536
Joined: Thu Jan 16, 2014 2:41 am
cars: 2004 Colorado 4.8L swap
86/90 Jimmy 6.5L diesel swap
80 Chevrolet Silverado TBI swap
88dodge W100 LPG conversion

Re: Enabling mixed frame and or extended Low Speed CAN single wire frames like those posted on GMLAN bible

Post by 04colyZQ8 »

low speed works to.. just doesn't seem to be getting the extended packets?
Option 7 debug is ONLY for when your saving to a file in case of lag to file, shouldn't be needed
When creating your own filters for CAN you need to add the 5 preceding zeros(000007E8,00000241,etc
1 - Log data for Engine ECU(7E0,7E8,7DF,101):
2 - Log data for Transmission ECU(7E2,7EA,7DF,101):
3 - Log data for Engine AND Transmission ECU(7E0,7E8,7E2,7EA,7DF,101):
4 - Log data for BCM ECU(241,641,541,7DF,101):
14 - Log data for BCM AND ECM ECU(241,641,541,7E0,7E8,7DF,101):
5 - Log data for with ID's you define, ex.000007E0/000007E2/00000101
6 - Log ALL data
7 - Debug enabled, data captured will scroll on screen when saving to file
8 - Exit
9 - No log file created, just show on screen. Press 9 to change
10 - Logging GM lan(Low speed pin 1), press 10 to change
11 - Currently CAN_ID_NONE for ConnectFlag, press 11 to change
6
1 - MDI
2 - MDI 2
3 - MongoosePro GM II

Input Device Number:3
Press the p key to pause log, all monitoring will pause
Press any key to stop logging
starting log in 1 second
Starting log
[00:00:05.3262416] : 00000100
[00:00:05.4071659] : 000006210140000000000000