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

NO

DTCs listed below are stored in the scan tool

P1185/P1186/P1187/P1188/P1189

Check items with the scan tool and the multimeter

① Wiring harness inspection

② Check the leakage in the fuel line

③ Check the fuel pressure and the fuel pressure regulator current data

Specification :

Erase the DTC and then start the engine

IS THE ENGINE RUNNING ?

YES

NO

Follow the test drive condition as below :

Test drive condition

① Fix the fuel pressure and the fuel pressure regulator current data (graph)

② Let it idle after depressing the accel pedal from the idling to 3000 rpm

③ Check the fuel pressure and fuel pressure regulator current data

Check the voltage at the rail pressure sensor terminal 2 while idling.

IS THERE approx. 4.5 V OR HIGER CONTINUOUSLY ?

YES

NO

a.

Intermittent failure, system is O.K at this time.

b.

Go to step 6

Check the signal waveform at the rail pressure sensor terminal 2 after depressing the accel pedal fully.

IS THERE THE SIGNAL WAVEFORM PROPERLY DISPLAYED ?

YES

NO

a.

Replace the rail pressure sensor after checking the wiring harness. For a detailed inspection procedure, refer to " DTC P0192 ~ 0194 "

WAVEFORM ANALYSIS

This test should be inspected after depressing the HOLD mode from run during the idling, acceleration and deceleration. The waveform pattern become increasing upward rapidly when the engien speed increases. If the waveform pattern becomes distorted during the acceleration or deceleration, replace the RPS

Check the DTC.

IS DTC P1189 INDICATED ?

YES

NO

MONITORING FOR PENDING DTC SET ?

YES

NO

Erase the DTC and then start the engine

Test drive condition

① Fix the fuel pressure current data (graph)

② Let it idle after depressing the accel pedal from the idling to 2400 rpm

③ Check the fuel pressure and fuel pressure regulator current data

IS THERE THE FUEL PRESSURE KEEP ABOVE 120 bar ?

YES

NO

a.

Inspect the fuel line leakage

b.

Inspect the fuel quality and the electric fuel pump and filter

c.

Check the low pressure and the high pressure fuel line system. For inspecting the fuel line system, Go to "Component Inspection" procedure

d.

Go to step 3

Start the engine

Test drive condition

Hold the engine speed 3000 rpm for more than 3 seconds and check the fuel pressure current data.

IS THERE THE FUEL PRESSURE KEEP ABOVE 200 bar ?

YES

NO

Check the DTC

IS DTC P1186 INDICATED ?

YES

NO

Perform the test drive and check the DTC

MONITORING FOR PENDING DTC SET ?

YES

NO

Erase the DTC and then start the engine

Test drive condition

① Fix the fuel pressure and the fuel pressure regulator current data (graph)

② Let it idle after depressing the accel pedal from the idling to 3000 rpm

③ Check the fuel pressure and fuel pressure regulator current data

DOSE THE FUEL PRESSURE KEEP ABOVE 250 bar WITH THE ABOVE 10% OF FUEL PRESSURE DUTY RATIO REGULATOR DUTY ?

YES

NO

a.

Inspect the fuel line leakage

b.

Inspect the fuel quality and the electirc fuel pump and filter

c.

Inspect the fuel pressure regulator sticking

d.

Check the low pressure and the high pressure fuel line system. For inspecting the fuel line system, Go to "Component Inspection" procedure

e.

Go to step 3

Check the DTC

IS DTC P1186 INDICATED ?

YES

NO

Perform the test drive and check the DTC.

MONITORING FOR PENDING DTC SET ?

YES

NO

Erase the DTC and then start the engine

Test drive condition

① Fix the fuel pressure and the fuel pressure regulator current data (graph)

② Let it idle after depressing the accel pedal from the idling to 3000 rpm

③ Check the fuel pressure and fuel pressure regulator current data

DOSE THE FUEL PRESSURE KEEP ABOVE 250 bar WITH THE ABOVE 10% OF FUEL PRESSURE DUTY RATIO REGULATOR DUTY ?

YES

NO

a.

Inspect the fuel line leakage

b.

Inspect the fuel quality and the electirc fuel pump and filter

c.

Inspect the fuel pressure regulator leakage

d.

Inspect the injector

e.

Check the low pressure and the high pressure fuel line system. For inspecting the fuel line system, Go to "Component inspection" procedure

f.

Go to step 3

Check the DTC

IS DTC P1188 INDICATED ?

YES

NO

Perform the test drive and check the DTC

MONITORING FOR PENDING DTC SET ?

YES

NO

Erase the DTC and then start the engine

IS THERE THE ENGINE RUNNING ?

YES

NO

Follow the test drive condition as below :

Test drive condition

① Fix the fuel pressure and the fuel pressure regulator current data (graph)

② Let it idle after depressing the accel pedal from the idling to 3000 rpm

③ Check the fuel pressure and fuel pressure regulator current data

Check the voltage at the rail pressure sensor terminal 2.

IS THERE approx. 1 V ?

YES

NO

a.

Replace the rail pressure sensor after checking the wiring harness. For a detailed inspection procedure, refer to " DTC P1182/1183/1184 "

b.

Go to step 6

Check the waveform at the rail fuel pressure terminal 2 after depressing the accel pedal fully.

IS THERE THE SIGNAL WAVEFORM PROPERLY DISPLAYED ?

YES

NO

a.

Replace the rail pressure regulator after checking the wiring harness

b.

For a detailed inspection procedure, refer to " DTC P0192 ~ 0194 "

c.

Go to step 8

WAVEFORM ANALYSIS

This test should be inspected after depressing the HOLD mode from run during the idling, acceleration and deceleration. The waveform pattern become increasing upward rapidly when the engien speed increases. If the waveform pattern becomes distorted during the acceleration or deceleration, replace the RPS

Check the DTC.

IS DTC P1189 INDICATED ?

YES

NO

MONITORING FOR PENDING DTC SET ?

YES

NO