If your engine is knocking the sound with be at the bottom of your oil pan but if you have lifter or rocker arm problems the sound will be at the top of your engine. One other thing you said your car has 315k it might be time to change your oil pump.
the fuse is blown. check your fuses may say htd-st. they could be inside fuse box or engine compartment fuse box. im sure its a blown fuse. mine blow if i leave seat on to long. I put a bigger (higher amp) in mine no more problem