Greetings,
Some electrical troubleshooting tips:
--
With a voltage meter (analog or DVOM), if not auto-range, making sure setting is above (12) volts reading,
With negative probe on Battery Negative (-) terminal, test each side of the 80 Amp fuse, make sure you are getting (+) voltage through the fuse / the fuse is not blown.
With positive probe on Battery Positive (+) terminal, touch Negative probe to:
Battery tray ground point (at base of battery, between battery and Intake Manifold,
Engine ground point (follow ground strap (wire) from battery tray ground point -> mounting location on Intake Manifold,
Both should test out at approx. Battery voltage, within .2 volts. If not, suspect a Ground issue and clean all connections / bolts / ground rings, see below..
Recommend restoring wiring back to factory-stock condition / cleaning engine compartment ground points:
--- With battery disconnected / out of vehicle: ---
Disconnect any AFTERMARKET electrical items, (Interior / aux. Exterior lighting, trailer wiring, stereo, amps / subs, alarms, remote car start) - RESET wiring back to factory-stock before proceeding..
--
Pos. and Neg. terminals, and the connection bolts / rings, if you have the (2) piece terminal setup, e.g. terminal bolts to connection point at end of Pos.and/or Neg. cable..
Battery tray ground point bolt and ground rings,
Battery tray ground -> frame ground bolts - remove battery, lift out plastic battery tray, if present, you will see (3) or (4) bolts securing the ground tray to frame.. Some models have a (separate) ground tray, some are formed/welded directly in, if you see bolts holding the tray to the frame, remove, cleanup or (replace) any rusted bolt hardware / the tray bottom and contact point on frame, coat w/ dielectric grease and reinstall..
Engine ground strap ground ring @ Intake Manifold & connection point on manifold,
Use a brass wire brush, and/or fine-grit sandpaper (200-400 grit), clean the connections bright, use a light coat of dielectric grease on all connections before re-assembly..
As long as the battery is out, and you have the tools available, consider cleaning the (Positive) feed ground rings for the Alt/Main fuse as well.. A thin popsicle stick w/ fine grit sandpaper wrapped around, or a donor emery board works well here to get to the underside of the ring / fuse box contact points,
--
If no joy, disconnect battery again, consider (removing) and cleaning up the blades of the MAIN and FUEL PUMP relays, re-insert, reconnect battery and test for positive effect..
--
If improvement, consider purchasing replacement Relays from KIA, use dealer-part only,
If still no joy, consider a wiring issue that may have been exasperated when you disturbed and/or moved the engine compartment fuse box in the process of replacing the main (alt) fuse..
With battery connected, engine off, key out of ignition:
If still no joy, with the voltmeter, check all fuses in the engine compartment for voltage, noting any which do not have power, and do the same for all fuses in the engine compartment fuse box..
--
Is it possible that the battery was installed incorrectly / reverse at some point when the battery was changed over? That would blow the Alt/Main 80 Amp fuse for sure, and would warrant checking (all) fuses / ground points above.
Hope this helps,
GottaCruise