Enable Highway Cruise on 1227747 ECM

[RobertISaar]

the high gear test option will basically disable highway spark in anything less than 4th gear(assuming a 4 speed) based on the 4th gear switch status, if it's selected. obviously only used on automatics, and those that have gear indication switches at that. some 4T60s(FWD) have a gear switch for 2nd, 3rd and 4th gears, to let the ECM know what gear the transmission is actually in at all times.

in some masks, highway spark is REQUIRED to be active before higheay fuel can be enabled. i usually modify my vehicles so that if one is active, the other must be active as well. if one deactivates, the other must deactivate at the same time. essentially turning the highway spark stuff into highway fuel added spark, since highway spark can normally be active WITHOUT highway fuel.

[sfara002]

I know this is kind of an old thread but I am trying this out on my 91 GMC Full size Jimmy. The standard bin is the ARJT and I have modified with the HW lean cruise and ESC as per the instructions on this thread. When I did a bin differences and even noted the which I though appeared similar to what was posted here. However; when I loaded the ECM I immediately got a rapid flashing Service Engine Soon light. I tried the load on several different 512 chips with the same result. The standard ARJT bin works fine. I would take any suggestions at this point. I have uploaded my modified bins as per these instructions for reference. I am just trying to apply the HW lean cruise to the standard ARJT bin at this point and data log at a later date for fine tuning.

Thanks in Advance,
Steve

[ony]

down load the latest xdl for the 7747 then on the parimater tree it has patches an it takes the guess work out of appling the patch. I would also apply the bpw patch. the file is on this site. you should read some of the threads about hlc patch so not to damage your vehicale.