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So is this an issue with all the 2021 GM vehicles or what? I'd dealing with a truck but wonder if the cars are like this too. You can scan via the OBD port but can't write to the ECU. I had to make a ECU wiring harness to plug directly into the ECU to write to it. This is driving me nuts. Takes me 10-15min every time I reflash this vehicle. Is everyone having this issue on all 2021's?
Global B or VIP architecture have most or all modules isolated by the serial data gateway module.
All CAN messages go through the SDGM to make sure they have the correct security protocol.
If I was you splice into the CAN wires in the harness right by the ECU and just have a second OBD port, could that be a work around?
What kind of vehicle is it? I know that some of the supported GM vehicles run into trouble with the serial gateway module blocking any comms from tools trying to do non OE things.Quote:
Originally Posted by C5turbo
Quote:
Originally Posted by cadillactech
hpt doesn't support any Global B applications yet. However, some Global A vehicles also use a wholly isolated gateway module. The 2021 Colorados have that as do some other vehicles.
Yep, it's a Colorado/Canyon truck.
Ya, I meant to say many other Global A vehicles the SDGM as well. OE's are all over CAN bus security now.Quote:
Originally Posted by tunerpro
You might be able to wire in a dedicated DLC for the ECM/TCM but it may mess with the CAN bus as you would still be tapped in to the other modules on that isolated bus.Quote:
Originally Posted by C5turbo
If you do try, let us know if it works!
GM added a security module(similar do 2018+ dodge) that needs to be bypassed in order to read/flash. Currently the only way is to read/flash via bench harness in those applications.Quote:
Originally Posted by C5turbo