DTC P1235-13: High Pressure Fuel Pump Circuit Open [06/2018 - 08/2020]: Description

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The high-pressure direct injection fuel system consists of a spill control valve, check valve, fuel relief valve, fuel pressure sensor (for high pressure side), fuel pump assembly (for high pressure side) and direct fuel injector assemblies. The spill control valve adjusts the return volume of the high-pressure fuel. The check valve mechanically opens and closes the paths to the fuel delivery pipes. The relief valve releases the fuel back to the fuel tank if the high-pressure fuel system malfunctions. The fuel pump assembly (for high pressure side) is installed to the cylinder head cover and operated by a cam installed to the end of the exhaust camshaft. Rotation of the camshaft moves the pump plunger inside the fuel pump assembly (for high pressure side) up and down, pressurizing the fuel. The pressurized fuel opens the check valve and is pumped into the fuel delivery pipe.

DTC No.	Detection Item	DTC Detection Condition	Trouble Area	MIL	Memory	Note
P1235-13	High Pressure Fuel Pump Circuit Open	Open or short in fuel pump assembly (for high pressure side) circuit detected 60 times or more (1 trip detection logic).	Open or short in fuel pump assembly (for high pressure side) circuit Fuel pump assembly (for high pressure side) ECM	Comes on	DTC stored	SAE Code: P1235