P1235
FA20 ENGINE CONTROL: SFI SYSTEM: P1235; High Pressure Fuel Pump Circuit; 2013 MY FR-S [03/2012 -]
P1235 - High Pressure Fuel Pump Circuit
DESCRIPTION
The fuel pump assembly (for high pressure) is attached to the insulator, which is attached to the cylinder head cover. The pump activates according to the position of the cam on the intake side camshaft (bank 2).
The fuel pump assembly (for high pressure) increases the pressure of the fuel supplied from the fuel pump in the fuel tank to the specified fuel pressure according to the operating condition, and it feeds the fuel to the fuel delivery pipe.
MONITOR STRATEGY
TYPICAL ENABLING CONDITIONS
TYPICAL MALFUNCTION THRESHOLDS
CONFIRMATION DRIVING PATTERN
1. Connect the Techstream to the DLC3.
2. Turn the ignition switch to ON and turn the Techstream on.
3. Record the Freeze Frame Data.
4. Clear the DTCs (even if no DTCs are stored, perform the clear DTC procedure) Reading and Clearing Diagnostic Trouble Codes.
5. Turn the ignition switch off and wait for at least 30 seconds.
6. Turn the ignition switch to ON and turn the Techstream on.
7. Based on engine speed, engine load and other freeze frame data stored in the ECM, reproduce the conditions present when the DTC was stored.
8. Enter the following menus: Powertrain / Engine / Trouble Codes.
9. Read the DTC.
HINT
* If a DTC is output, the system is malfunctioning.
* If a DTC is not output, perform the following procedure.
10. Enter the following menus: Powertrain / Engine / Utility / All Readiness.
11. Input the DTC: P1235.
12. Check the DTC judgment result.
HINT
* If the judgment result shown ABNORMAL, the system has a malfunction.
* If the judgment result shows NORMAL, the system is normal.
13. If the test result is INCOMPLETE or N/A and no DTC is output, perform a universal trip and check for permanent DTCs Reading and Clearing Diagnostic Trouble Codes.
HINT
* If a permanent DTC is output, the system is malfunctioning.
* If no permanent DTC is output, the system is normal.
WIRING DIAGRAM
INSPECTION PROCEDURE
HINT
* If the current from the INJ relay is cut because DTC P062D is stored, DTC P1235 will be stored even if the fuel pump assembly (for high pressure) is normal.
* Read freeze frame data using the Techstream. The ECM records vehicle and driving condition information as freeze frame data the moment a DTC is stored. When troubleshooting, freeze frame data can help determine if the vehicle was moving or stationary, if the engine was warmed up or not, if the air fuel ratio was lean or rich, and other data from the time the malfunction occurred.
PROCEDURE
1. INSPECT FUEL PUMP ASSEMBLY (FOR HIGH PRESSURE)
(a) Inspect the fuel pump assembly (for high pressure) Inspection.
NG -- REPLACE FUEL PUMP ASSEMBLY (FOR HIGH PRESSURE) Removal
OK -- Continue to next step.
2. CHECK HARNESS AND CONNECTOR (INJECTOR DRIVER (EDU) - FUEL PUMP ASSEMBLY)
(a) Disconnect the injector driver (EDU) connector.
(b) Disconnect the fuel pump assembly (for high pressure) connector.
(c) Measure the resistance according to the value(s) in the table below.
Standard Resistance (Check for open):
Standard Resistance (Check for short):
NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- Continue to next step.
3. CHECK HARNESS AND CONNECTOR (ECM - INJECTOR DRIVER (EDU))
(a) Disconnect the ECM connector.
(b) Disconnect the injector driver (EDU) connector.
(c) Measure the resistance according to the value(s) in the table below.
Standard Resistance (Check for open):
Standard Resistance (Check for short):
NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- Continue to next step.
4. INSPECT ECM (FPD VOLTAGE)
(a) Turn the ignition switch to ON.
(b) Inspect the ECM using an oscilloscope.
(1) While idling the engine, check the waveform the terminals of the ECM connector.
Standard:
Signal waveform appears as shown in the illustration.
HINT
The FPD terminal waveform is output only right after the engine starts. If this DTC is stored when the engine is started from ignition switch off, the system enters fail-safe mode and the waveform is not output.
NG -- INSPECT ECM (FPD VOLTAGE)
OK -- Continue to next step.
5. INSPECT ECM (FPF VOLTAGE)
(a) Turn the ignition switch to ON.
(b) Inspect the ECM using an oscilloscope.
(1) While idling the engine, check the waveform the terminals of the ECM connector.
HINT
*: If the FPF terminal waveform is similar to the FPF terminal waveform NG waveform 1, stop the engine and disconnect injector driver (EDU) connector. Then, while cranking the engine, check to see if there is a difference between the FPF terminal waveform and the previous one.
Result:
B -- REPLACE INJECTOR DRIVER (EDU) Removal
A -- REPLACE ECM Removal
6. INSPECT ECM (FPD VOLTAGE)
(a) Turn the ignition switch to ON.
(b) Disconnect the injector driver (EDU) connector.
(c) Inspect the ECM using an oscilloscope.
(1) While cranking the engine, check the waveform the terminals of the ECM connector.
Standard:
Signal waveform appears as shown in the illustration.
NG -- REPLACE ECM Removal
OK -- REPLACE INJECTOR DRIVER (EDU) Removal