I cannot find a P00 are you sure it is not a PQ0.
The following is for a PQ0
Replacement parts for Whirlpool LER5636PQ0 29"ELECTRIC DRYER | AppliancePartsPros.com
See the attachment for the tech sheet. It includes a timing diagram.
Could be a couple things
Place timer at the ends of a cycle when cool down should happen.
Unplug the unit. Check the timer contacts BK/R.
They should be infinite ohms (open).
Be sure to disconnect the wires to one of the connectors when checking it. This prevents you from reading an alternate/parallel circuit path.
Remove both wire from the heating coil.
Check it with the meter, should be 8 to 12 ohms.
Then measure from each heating coil connector to a bare spot on the frame. Both should be infinite ohms.
If not then the element is grounded and always on.