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DTC P0191-00: Fuel Pressure Sensor Circuit Range/Performance Problem: Notes

DETECTION CONDITION AND POSSIBLE CAUSE

DTC P0191:00	Fuel pressure sensor circuit range/performance problem
DETECTION CONDITION	The difference between the actual and target fuel pressure is equal to or more than the specification, even though the fuel pressure feedback amount is maintained low or high. Diagnostic support note This is a continuous monitor (CCM). The check engine light illuminates if the PCM detects the above malfunction condition during the first drive cycle. FREEZE FRAME DATA (Mode 2)/Snapshot data is available. The DTC is stored in the PCM memory.
FAIL-SAFE FUNCTION	Stops the high pressure fuel pump control. Limits the intake air amount.
POSSIBLE CAUSE	Fuel pressure sensor connector or terminals malfunction Short to ground in wiring harness between the following terminals: Fuel pressure sensor terminal C-PCM terminal 1BJ Fuel pressure sensor terminal B-PCM terminal 1CA PCM connector or terminals malfunction Short to power supply in wiring harness between fuel pressure sensor terminal B and PCM terminal 1CA Fuel pressure sensor circuits are shorted to each other Open circuit in wiring harness between the following terminals: Fuel pressure sensor terminal C-PCM terminal 1BJ Fuel pressure sensor terminal B-PCM terminal 1CA Fuel pressure sensor terminal A-PCM terminal 1CB Fuel pressure sensor malfunction High pressure fuel pump malfunction PCM malfunction

CAUTION:

Verify the malfunction symptom according to not only the PID value but also the symptom troubleshooting.

RELATED PIDS

Monitor item (Definition)	Unit/Condition	Condition/Specification (Reference)
FUEL_PRES	KPa {MPa}, mBar {Bar}, psi, in H20	Displays the fuel pressure
FUEL_PRES	V	Fuel pressure is 3.0 MPa {31 kgf/cm ² , 435 psi}: approx. 0.92 V Fuel pressure is 4.8 MPa {49 kgf/cm ² , 696 psi}: approx. 1.17 V
LOAD	%	Idle (after warm up): approx. 16.07 % Racing (engine speed is 2,000 rpm): approx. 14.51 % Racing (engine speed is 4,000 rpm): approx. 21.17 %
RPM	RPM	Displays the engine speed