There are several reasons for high oil pressure to occur in a Jeep, such as a bad oil sending unit. Since this unit is powered by electricity, it may not work if electricity does not reach it.
If electricity is moving into the sending unit, another reason high oil pressure may occur is due to a stuck oil pressure release valve. Removing, cleaning and replacing the valve is the solution to this issue. If this action does not lower the pressure, something else, such as a blocked oil passage, is causing the high oil pressure. This is a serious problem that can cause long-term engine damage.