| DTC Code | DTC Name |
|---|---|
| P0191 | Fuel Rail Pressure Sensor Circuit Range / Performance |
DESCRIPTION
The ECM monitors the internal fuel pressure of the common rail using the fuel pressure sensor, and controls the suction control valve to regulate the common rail pressure so that it reaches the target pressure determined by the ECM. The pressure sensor is a semiconductor that varies its electrical resistance when pressure is applied to its silicon chip. This sensor outputs a voltage in proportion to the common rail fuel pressure.
| DTC No. | Detection Item | DTC Detection Condition | Trouble Area | MIL | Memory |
|---|---|---|---|---|---|
| P0191 | Fuel Rail Pressure Sensor Circuit Range / Performance | The difference between the main and sub voltage outputs of the fuel pressure sensor is 0.04 V or less, or 1.06 V or higher for 1 second or more (1 trip detection logic). |
|
Comes on | DTC stored |
| DTC No. | Data List |
|---|---|
| P0191 |
|
CONFIRMATION DRIVING PATTERN
| DTC Detection Drive Pattern | Idling for 1 second |
WIRING DIAGRAM
Refer to DTC P0087 Click here.
CAUTION / NOTICE / HINT
Note
After replacing the ECM, the new ECM needs registration (See page ) and initialization Click here.
PROCEDURE
READ VALUE USING GTS (COMMON RAIL PRESSURE AND TARGET COMMON RAIL PRESSURE)
Connect the GTS to the DLC3.
Turn the ignition switch to ON and turn the GTS on.
Enter the following menus: Powertrain / Engine / Data List / Common Rail Pressure and Target Common Rail Pressure.
| Tester Display |
|---|
| Target Common Rail Pressure |
| Common Rail Pressure |
Start the engine.
Check the change in the values for the Data List items above when increasing the engine speed from idling to 3000 rpm with no load.
| Result | ||||||
|---|---|---|---|---|---|---|
|
Tech Tips
Normally, "Common Rail Pressure" is within 5000 kPa of "Target Common Rail Pressure".
| B |
|
GO TO STEP 4 Click here |
| A |
|
CHECK HARNESS AND CONNECTOR (FUEL PRESSURE SENSOR - ECM)
Disconnect the fuel pressure sensor connector.
Disconnect the ECM connector.
Measure the resistance according to the value(s) in the table below.
| Standard Resistance | |||||||||||||||||||||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
|
Reconnect the fuel pressure sensor connector.
Reconnect the ECM connector.
| Result | |||
|---|---|---|---|
|
| OK |
|
GO TO STEP 5 Click here |
| NG |
|
REPAIR OR REPLACE HARNESS OR CONNECTOR
Repair or replace the harness or connector.
| Result | ||
|---|---|---|
|
| NEXT |
|
CHECK WHETHER DTC OUTPUT RECURS (DTC P0191)
Connect the GTS to the DLC3.
Turn the ignition switch to ON and turn the GTS on.
Clear the DTCs.
Let the engine idle for 1 second.
Enter the following menus: Powertrain / Engine / Trouble Codes.
Read the DTCs.
| Result | ||||||
|---|---|---|---|---|---|---|
|
| B |
|
END |
| A |
|
REPLACE COMMON RAIL ASSEMBLY
Replace the common rail assembly.
| Result | ||
|---|---|---|
|
| NEXT |
|
BLEED AIR FROM FUEL SYSTEM
Bleed the air from the fuel system.
| Result | ||
|---|---|---|
|
| NEXT |
|
CHECK WHETHER DTC OUTPUT RECURS (DTC P0191)
Connect the GTS to the DLC3.
Turn the ignition switch to ON and turn the GTS on.
Clear the DTCs.
Let the engine idle for 1 second.
Enter the following menus: Powertrain / Engine / Trouble Codes.
Read the DTCs.
| Result | ||||||
|---|---|---|---|---|---|---|
|
| B |
|
END |
| A |
|
REPLACE ECM
Replace the ECM.
| Result | ||
|---|---|---|
|
| NEXT |
|
CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIRED
Connect the GTS to the DLC3.
Turn the ignition switch to ON and turn the GTS on.
Clear the DTCs.
Let the engine idle for 1 second.
Enter the following menus: Powertrain / Engine / Trouble Codes.
Confirm that the DTC is not output again.
| Result | ||
|---|---|---|
|
| NEXT |
|
END |