DESCRIPTION
| DTC Detection Drive Pattern | DTC Detection Condition | Trouble Area |
|---|---|---|
| Idling for 60 seconds | The actual fuel pressure exceeds the target fuel pressure by 5000 kPa or more for 10 seconds (1 trip detection logic). |
|
| DTC No. | Data List |
|---|---|
| P1229 |
|
Tech Tips
For more information on the fuel supply pump assembly (suction control valve) and common rail system, refer to System Description Click here.
When DTC P1229 is stored, check the internal fuel pressure of the common rail by entering the following menus: Powertrain / Engine and ECT / Data List / Fuel Press, Target Common Rail Pressure.
Under a stable condition such as idling or running the engine at 2500 rpm without load, Fuel Press is within 5000 kPa of Target Common Rail Pressure when normal.
When there is a problem with the movement of the fuel supply pump assembly (when Fuel Press is higher than Target Common Rail Pressure due to a problem in which the suction valve has difficulty closing), the values of Injection Pressure Correction decrease.
MONITOR DESCRIPTION
P1229 (Fuel over-feed):The ECM sets this DTC if the actual fuel pressure inside the common rail remains higher than the target fuel pressure, despite the ECM closing the suction control valve. This DTC indicates that the suction control valve may be stuck open, or that there may be a short circuit. Under this condition, the pressure discharge valve operates frequently.
If this DTC is set, the ECM enters fail-safe mode and limits the engine power. The fail-safe mode continues until the ignition switch is turned off.
WIRING DIAGRAM
INSPECTION PROCEDURE
Tech Tips
Read freeze frame data using the intelligent tester. Freeze frame data records the engine condition when malfunctions are detected. When troubleshooting, freeze frame data can help determine if the vehicle was moving or stationary, if the engine was warmed up or not, and other data from the time the malfunction occurred.
When this DTC is stored, be sure to carefully examine "Fuel Press" and "Target Common Rail Pressure" in the freeze frame data.
PROCEDURE
CHECK OTHER DTC OUTPUT
Connect the intelligent tester to the DLC3.
Turn the ignition switch to ON and turn the tester on.
Enter the following menus: Powertrain / Engine and ECT / DTC.
Read the DTCs.
| Result | Proceed to |
|---|---|
| P1229 and "P0190, P0192 and/or P0193" | B |
| Except above | A |
| B |
|
GO TO FUEL RAIL PRESSURE SENSOR CIRCUIT Click here |
| A |
|
READ VALUE USING INTELLIGENT TESTER (FUEL PRESS AND TARGET COMMON RAIL PRESSURE)
Connect the intelligent tester to the DLC3.
Turn the ignition switch to ON and turn the tester on.
Start the engine and warm it up.
Enter the following menus: Powertrain / Engine and ECT / Data List / Fuel Press and Target Common Rail Pressure.
Check that the internal fuel pressure of the common rail is within the specification below.
| OK |
|---|
| Fuel Press is within 5000 kPa of Target Common Rail Pressure when engine is idling. |
| NG |
|
CHECK HARNESS AND CONNECTOR (SUCTION CONTROL VALVE - ECM) Click here |
| OK |
|
CHECK FOR INTERMITTENT PROBLEMS Click here
CHECK HARNESS AND CONNECTOR (SUCTION CONTROL VALVE - ECM)
Disconnect the suction control valve connector.
Disconnect the D71 ECM connector.
Measure the resistance according to the value(s) in the table below.
| Standard Resistance (Check for Open) | |||||||||
|---|---|---|---|---|---|---|---|---|---|
|
| Standard Resistance (Check for Short) | |||||||||
|---|---|---|---|---|---|---|---|---|---|
|
| OK |
|
CLEAN FUEL FILTER CASE AND REPLACE FUEL FILTER Click here |
| NG |
|
REPAIR OR REPLACE HARNESS OR CONNECTOR Click here |
REPAIR OR REPLACE HARNESS OR CONNECTOR
Repair or replace the harness or connector.
| NEXT |
|
PERFORM ACTIVE TEST USING INTELLIGENT TESTER (TEST THE FUEL LEAK)
Connect the intelligent tester to the DLC3.
Turn the ignition switch to ON and turn the tester on.
Enter the following menus: Powertrain / Engine and ECT / Active Test / Test the Fuel Leak / Data List / Fuel Press, Target Common Rail Pressure.
Take a snapshot with the intelligent tester during the Active Test.
Tech Tips
Detailed graphs can be displayed by transferring the stored snapshot from the tester to a PC (personal computer) with Intelligent Viewer installed.
Measure the difference between the target fuel pressure (Target Common Rail Pressure) and the actual fuel pressure (Fuel Press) when the "Test the Fuel Leak" Active Test is performed Click here.
Tech Tips
In order to obtain an exact measurement, perform the Active Test 5 times and measure the difference once each time the Active Test is performed.
| OK |
|---|
| The difference between the target fuel pressure and the actual fuel pressure 2 seconds after the Active Test starts is less than 10000 kPa. |
Tech Tips
"Target Common Rail Pressure" is the target fuel pressure controlled by the ECM.
"Fuel Press" is the actual fuel pressure.
| Result | Proceed to |
|---|---|
| The difference between the target fuel pressure and the actual fuel pressure 2 seconds after the Active Test starts is less than 10000 kPa. | B |
| Except above | A |
| B |
|
CHECK CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIRED Click here |
| A |
|
CLEAN FUEL FILTER CASE AND REPLACE FUEL FILTER
Clean the fuel filter case and replace the fuel filter.
Tech Tips
Be sure to clean the inside of the fuel filter case as the fuel injectors may not operate properly if the fuel filter is installed with foreign matter remaining inside the fuel filter case.
| NEXT |
|
REPLACE SUCTION CONTROL VALVE
Replace the suction control valve Click here.
| NEXT |
|
BLEED AIR FROM FUEL SYSTEM
Bleed the air from the fuel system Click here.
| NEXT |
|
PERFORM FUEL SUPPLY PUMP ASSEMBLY INITIALIZATION
Perform fuel supply pump assembly initialization Click here.
| NEXT |
|
CHECK CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIRED
Connect the intelligent tester to the DLC3.
Clear the DTCs Click here.
Turn the ignition switch off for 30 seconds or more.
Start the engine.
Idle the engine for 60 seconds, and then run it at 2500 rpm without load for 60 seconds.
Confirm that the DTC is not output again.
Tech Tips
Perform the following procedure using the tester to determine whether or not the DTC judgment has been carried out.
Enter the following menus: Powertrain / Engine and ECT / Utility / All Readiness.
Input DTC P1229.
Check that STATUS is NORMAL. If STATUS is INCOMPLETE or UNKNOWN, increase the idling time.
| NEXT |
|
END