Problem:
It’s a GM Delco E98 ECM. Read it on a CG FC200 programmer on bench mode. Then disabled DPF EGR OFF and wrote the file after checking it. The writing was successful, but now the ECU’s maintenance light isn’t working and the ECU isn’t responding.
Do not write or read at all.
Any solution?
Solution:
Bad flash.
CG FC200 is not very good at it (bench mode).
Try to recover this ECM in boot mode.
Boot mode and need seed key.
Use OBDSTAR DC706, i/O Terminal or trasdata to recover in boot mode.
You need to have the shadow password.
Here is the instruction on how to recover GM Delco ECMs with OBDSTAR DC706 in boot mode:

