Check for damaged harness and terminals including rubber seals :
contact resistance, oxidation, corrosion, bent or broken terminals
harness connector connection, loose wires etc.
Check for poor connection between ECM and component :
backed out terminal, improper mating, broken locks and poor terminal to wire connection
ARE THE WIRES O.K ? & ARE THE CONNECTIONS O.K ?
YES
Go to "Signal Circuit Inspection" procedure
NO
Repair as necessary and go to " Verification of Vehicle Repair " procedure
DTCs listed below are stored in the scan tool
P1182/P1183/P1184
Check items with the scan tool and the multimeter
① Wiring harness inspection
② Check the voltage from the ECM
③ Check the resistance
Specification
Resitance : below 1 Ω for open in the wire
Resitance : infinite for short to ground in the wire
Voltage : below 0.5V for short to power in the wire
Sensor supply voltage : Approx. 12V
Refer to the component and full circuit for connector configrations details
Disconnect the fuel pressure regulator and turn the ignition switch ON
measure the voltage at the FPR terminal 1.
ARE THERE THE BATTERY VOLTAGE FOR TERMINAL 1 AND 0V FOR TERMINAL 2 ?
YES
Intermittent failure, system is O.K at this time.Go to step 3
Check for poor connections or losse wire at the fuel pressure regulator and the ECM
Go to step 7
NO
Repair short in the wire between the fuel pressure regulator terminal 1 and the ECM teminal 27/C230-2.
Repair short in the wire between the fuel pressure regulator terminal 2 and the ECM terminal 28/C230-2.
Go to step 3
Measure the voltage at the ECM terminal 27/C230-2 after turning the ignition switch ON
IS THERE A BATTERY VOLTAGE ?
YES
Recheck short in the wire between the fuel pressure regulator terminal 1 and the ECM terminal 27/C230-2.
Go to step 5
NO
Replace a known - good ECM and recheck. If the battery voltage is checked, replace the ECM
Go to step 5
Connect the fuel pressure regulator and turn the ignition switch ON, measure the voltage between the FPR terminal 1 and the FPR terminal 2
IS THERE A BATTERY VOLTAGE ?
YES
Go to step 7
NO
Replace the fuel pressure regulator. For checking the fuel pressure regualtor, Go to "Component Inspection" procedure
Go to step 7
Connect the CH A probe of scan tool to the fuel pressure regulator terminal 2 after turning the ignition switch OFF and then start the engine
Check the FPR signal waveform when depressing the accel pedal fully one time.
IS THERE THE FUEL PRESSURE REGULATOR SIGNAL WAVEFORM PRORERLY DISPLAYED ?
YES
Go to "Verification of Vehicle Repair" procedure
NO
Recheck the wiring harness
Go to step 10
WAVEFORM ANALYSIS
This test should be inspected after depressing the HOLD mode at the operating range of FPR The time T becomes shorter when the FPR is opened increasingly. If the rectangular waveform pattern is distorted and omitted, replace the FPR. The cycle time T becomes shorter while idling. The rail pressure regulator is opening by the ECM duty control. The cycle time T becomes longer when accelerating. The rail pressure regulator is closing by the ECM duty control.
Connect the CH A probe of scan tool to the fuel pressure regulator terminal 28/C230-2 after turning the ignition switch OFF and then start the engine.
Check the FPR signal waveform when depressing the accel pedal fully one time.
IS THERE THE FUEL PRESSURE REGULATOR SIGNAL WAVEFORM PRORERLY DISPLAYED ?
YES
Recheck short in the wire between the fuel pressure regulator terminal 1 and the ECM terminal 27/C230-2. Go to "Verification of Vehicle Repair" procedure
NO
Replace a known - good ECM and recheck. If the signal waveform is displayed, replace the ECM. Go to "Verification of Vehicle Repair" procedure.
Disconnect the fuel pressure regulator and turn the ignition switch ON, measure the voltage at the FPR terminal 1.
ARE THERE THE BATTERY VOLTAGE FOR THE TERMINAL 1 AND 0 V FOR THE TERMINAL 2 ?
YES
Intermittent failure, system is O.K at this time.
Check for poor connections or losse wire at the fuel pressure regulator and the ECM
Go to step 7
NO
Repair open or short in the wire between the fuel pressure regulator terminal 1 and the ECM terminal 27/C230-2.
Repair open or short in the wire between the fuel pressure regulator terminal 2 and the ECM terminal 28/C230-2.
Go to step 3
Measure the voltage at the ECM terminal 27/C230-2 after turning the ignition switch ON.
IS THERE A BATTERY VOLTAGE ?
YES
Recheck open or short in the wire between the FPR terminal 1 and the ECM terminal 27/C230-2.
Go to step 5
NO
Replace a known - good ECM and recheck. If the battery voltage is checked, replace the ECM
Go to step 5
Connect the fuel pressure regulator and turn the ignition switch ON, measure the voltage between the FPR terminal 1 and the FPR terminal 2
IS THERE A BATTERY VOLTAGE ?
YES
Go to step 7
NO
Replace the fuel pressure regulator. For checking the fuel pressure regualtor , Go to "Component Inspection" procedure
Connect the CH A probe of scan tool to the fuel pressure regulator terminal 2 after turning the ignition switch OFF and then start the engine
Check the FPR signal waveform when depressing the accel pedal fully one time.
IS THERE THE FUEL PRESSURE REGULATOR SIGNAL WAVEFORM PRORERLY DISPLAYED ?
YES
Go to "Verification of Vehicle Repair" procedure
NO
Recheck the wiring harness
Go to step 10
WAVEFORM ANALYSIS
This test should be inspected after depressing the HOLD mode at the operating range of FPR The time T becomes shorter when the FPR is opened increasingly. If the rectangular waveform pattern is distorted and omitted, replace the FPR. The cycle time T becomes shorter while idling. The rail pressure regulator is opening by the ECM duty control. The cycle time T becomes longer when accelerating. The rail pressure regulator is closing by the ECM duty control.
Connect the CH A probe of scan tool to the fuel pressure regulator terminal 28/C230-2 after turning the ignition switch OFF and then start the engine.
Check the FPR signal waveform when depressing the accel pedal fully one time.
IS THERE THE FUEL PRESSURE REGULATOR SIGNAL WAVEFORM PRORERLY DISPLAYED ?
YES
Recheck open or short in the wire between the FPR terminal 1 and the ECM terminal 27/C230-2. Go to "Verification of Vehicle Repair" procedure
NO
Replace a known - good ECM and recheck. If the signal waveform is displayed, replace the ECM. Go to "Verification of Vehicle Repair" procedure
Measure the resistance of pressure regulator valve. For checking the fuel pressure regualtor , Go to "Component Inspection" procedure
Examine the system for the leakage.
Check the low and high pressure fuel line.
① Visually inspect for leakage and check all connector
② Block the fuel return line of the function block
③ Clog the fuel filter
Disconnect the electric connector from all injector and connect the scan tool.
Fix the fuel pressure and the feul pressure regulator current data.
Check the current data while operating the starting motor for 5 seconds
IS THERE MORE THAN 150 BAR IN THE FUEL PRESSURE ?
YES
Go to step 8
NO
Check the electric fuel pump
Check the high pressure pump
Check the injector. For checking the injector , Go to "P0261~ 0272 Component Inspection" procedure
Go to step 8
Connect the scan tool CH A probe to the fuel pressure regulator and CH B probe to the injector low side for the injector No.1 in order to check the signal waveform.
For checking the injector No.2,3,4, signal waveform, follow the above same procedure.
Check the fuel pressure regulator and the injector low side signal waveform while idling.
Check the fuel presure regulator and the injector low side signal waveform after turning the ignition switch OFF.
IS THERE NO THE INJECTOR LOW SIDE SIGNAL WAVEFOAM WITHOUT THE FUEL PRESSURE REGULATOR SUPPLY VOLTAGE AT THE SAME TIME ?
YES
Go to "Verification of Vehicle Repair" procedure
NO
Recheck the injector. For checking the injector , Go to "P0261~ 0272 Component Inspection" procedure
Replace a known - good ECM and recheck. If the problem is verified, replace the ECM
WAVEFORM ANALYSIS
This test should be inspected after depressing the HOLD mode while idling. After the ignition switch off, the FPR signal waveform is output even from the battery voltage to 0V and the injector signal waveform should be not generated by the ECM. If the FPR and the injector signal waveform are generated by the ECM, replace the ECM.
YES
Go to "Verification of Vehicle Repair" procedure