General Information

Engine Control
P0090 Fuel Pressure Regulator 1 Control Circuit/Open - General Information

Component Location





General Description

GDI(Gasoline Direct Injection) ECM calculates controlled variable with the signal from fuel rail pressure sensor to control optimized RPM and rail pressure. ECM sends it to IDB(Injector Drive Box). IDB operates fuel pressure valve according to controlled variable from ECM.
Two high pressure pumps pressurize fuel supplied from low pressure pump. Two fuel rail pressure regulator control fuel rail pressure at 35 - 150bar according to engine RPM.

DTC Description

When ECM detects open in the FPR control circuit, ECM sets DTC P0090.

DTC Detecting Condition





Diagnostic Circuit Diagram





Signal Waveform & Data




Fig.1) Normal waveform of FPR at idle.