: Communication with the MOTRONIC ECM

04-24-05, 04:52 AM
I have a 98 Catera and I hooked up a scanner I bought and pretty much all I could do was to retrieve any codes and it did a couple of component checks. I was wondering if anyone knows how to interface with the Motronic ECM that is in this Catera. I know it communicates using the ISO9141 Protocol. Anyone seen any hardware or software plans or diagrams on possibly making an interface to communicate to the ECM using some kind of software via my laptop? And I also see mentioned in the schematics of something called "Keyword 2000", it appears under "Serial Data" for the ECM output. Thanks. Below are a couple of pics of my ECM.

04-24-05, 08:52 PM
I dont know of any right now... but anyone (usually GM Mechanics) with a Tech II Diagnostic/Scan Tool can do it. They can tune out things like torque management and tweak settings.