Here are your parts
Replacement parts for LG LRE30451SW Electric Range | AppliancePartsPros.comHere is a service manual
LRE30451 LG Electric Range Repair Service Manual - ApplianceDigest.comYou have to join the site to download the manual but it is free and this is a very good site for manuals and other info for the appliance repair DIYer.
Sorry but am not sure what your problem is.
If unit is now totally dead, the first thing to check is the power.
Try flipping the breaker off/on slowly a couple times.
Sometimes you can loose half the line without actually tripping the breaker.
If this does nothing, check the voltage at the plug
L1 to L2 should be 240 volts
L1 to Neutral and L2 to Neutral, both should be 120 volts.
If OK
Unplug the unit and check the wires at the terminal strip in the machine to make sure none are loose or burned out
If OK
Check the power at the terminal strip.
Be careful as 240 volts is lethal !!!
If it is just the stove-top controls then I would try cleaning the connectors.
Be sure to unplug the unit while doing this.
Connector Cleaning / Checking
Unplug the unit
Open it up
Remove the ribbon cable from the keypad to the control board at the control board.
Clean the edge connector.
If it is the type where there is not a connector just the insulation is removed, it can be cleaned with a pencil eraser. Do not use an ink eraser as it is too abrasive.
Check the tracks in the ribbon cable for hairline cracks. A magnifying glass helps here.
Would not hurt to clean the connector on the board. Use electronics contact cleaner or isopropyl alcohol and a tooth brush. Be gentle and do not reconnect till all the solvent evaporates.
Reconnect everything and give it a try.