The check engine light gets power from the PCM - there is a PCM relay that gets power from a 10amp fuse number 6 and a 30amp fuse number 10 in the fuse box next to the battery. This can also affect the coil.
IT MEANS THERE IS A CIRCUIT ON YOUR IDEL AIR CONTROL VALVE THREE THINGS THAT COULD BE ONE ITS DISCONECTED OR ITS A BAD IDLE AIR CONTROL VALVE AND THREE THERE COULD BE A SHORT ON THE WIREING HARNESS OK HOPE THIS HELPS NEED MORE HELP LET ME KNOW THATS WHAT CODE P1504 MEANS
A poor connection to the battery can melt a cable. Make sure your battery terminal is clean and free from corrosion.Make sure that your battery lead has slack and that it is not taught, especially when the engine is revving.Make sure you don't over-tighten the soft battery terminal as it will over stress.