I am running a 7730 using a $A1 mask, Attempting to turn on Lean Cruise Mode 06C3 bit 7. After making the flag set and saving the bin. I burn the chip and reinstall in the ECM. Try connecting using ADL and will not communicate. Go thru the whole process again only turning off the flag and all is happy. With the bit set doing a compare bin with the non set bin. Compare does not note any differences. Could this not be the correct location or is there something else going on? I have searched and found nothing. Going on a long road trip tomorrow and would like to try and bump the MPG a little. Any ideas?
Mike

 

The $6C3 appears to be the correct location. Although when you did the compare that location along with the check sum should have been different. What did/does the SES light do at key-on, engine-off?

RBob.