Engine Reset without pulling battery terminal???
There is a way to reset the ECM without pulling the battery terminal.
The EFI fuse. Just pull this fuse and you have an ECM (hard) reset without having to reprogram radio stations, or reinitializing anything, pulling the battery terminal off.
How can this be? The EFI fuse supplies power to the ECM.
Also in todays modern age Car ECM's rarely need a hard reset.
Why? That is a good question. modern ECM's have processors that already are learning how to fuel a car within a couple of miles, when mods are added, dirty MAF that was cleaned, etc...
You can connect a scan tool and see this for yourself when CEL is cleared (that effects runability), the ECM will already start to compensate once the condition that set it is rectified.