What would have been GMs original design purpose to have a seperate location for the ECM/Fuel pump 20A fuse in a holder mounted by the battery? Everytime I open the hood I see it there and cant understand why GM didnt mount it in the normal fuse location or by the firewall. It has a long wire run in the harness loom but there has to be a reason for that design. Its good to pull the fuse if you feel youre needing to disable your car. But other than that who knows.

 

Two reasons I can think of:

1) Engineers want fuel pump to run for a second after ignition is shut off, so no need to run the wire into the interior.

2) Handy location to clear trouble codes.