(1).Check the oil pump for direction. If the direction is OK but no working pressure is delivered, stop it immediately. Please note: if the internal parts of the oil pump are not replaced at their original places after servicing when these parts are disassembled, the working pressure will not be produced even if the rotation is OK.
(2).Check if the overflow valve is blocked by foreign matters, and if the solenoid coil is connected properly.
(3).Check if the pressure gauge is damage, if so replace it.
(4).Check if the overflow valve is blocked by foreign matters, or if the spring of overflow valve is damaged.