P1235

4GR-FSE ENGINE CONTROL: SFI SYSTEM: P1235: High Pressure Fuel Pump Circuit
P1235 - High Pressure Fuel Pump Circuit

DESCRIPTION

The fuel pump 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 exhaust side camshaft (right bank).

The fuel pump for high pressure increases the pressure of the fuel supplied from the fuel pump in the fuel tank to 4 to 13 MPa (40.8 to 132.6 kgf/cm2, 580 to 1886 psi) according to the operating condition, and it feeds the fuel to the fuel delivery pipe.





MONITOR DESCRIPTION

The injector driver has the integrated circuit (IC) which monitors the electrical circuit between the spill control valve and injector driver. If an open circuit is detected, the IC sends the malfunction signal (FPD) to the ECM. Then, the ECM illuminates the MIL and sets a DTC immediately.

MONITOR STRATEGY





TYPICAL ENABLING CONDITIONS





TYPICAL MALFUNCTION THRESHOLDS





CONFIRMATION DRIVING PATTERN





- Connect the Techstream to the DLC3.

- Turn the engine switch on (IG) and turn the Techstream on.

- Clear the DTCs (even if no DTCs are stored, perform the clear DTC procedure) DTC Check / Clear.

- Turn the engine switch off.

- Turn the engine switch on (IG) and turn the Techstream on [A].

- Start the engine.

- Idle the engine for 10 seconds [B].

- Enter the following menus: Powertrain / Engine / Utility / All Readiness.

- Input the DTC: P1235.

- Check the DTC judgment result [C].





HINT
- If the judgment result shows ABNORMAL, the system has a malfunction.
- If the judgment result shows INCOMPLETE or UNKNOWN, perform steps [B] and [C] again.
- If the test result is UNKNOWN, enter the following menus: Powertrain / Engine / Trouble Codes / Pending.

- Read Pending DTCs.

HINT
If a pending DTC is output, the system is malfunctioning.

- If the test result is INCOMPLETE or UNKNOWN and no pending DTC is output, perform a universal trip and check for permanent DTCs DTC Check / Clear.

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
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 FOR HIGH PRESSURE

(a) Disconnect the fuel pump for high pressure connector.





(b) Measure the resistance according to the value(s) in the table below.

Standard Resistance:





Text in Illustration





(c) Reconnect the fuel pump for high pressure connector.

NG -- REPLACE FUEL PUMP FOR HIGH PRESSURE Removal
OK -- Continue to next step.

2. CHECK HARNESS AND CONNECTOR (INJECTOR DRIVER - FUEL PUMP FOR HIGH PRESSURE)

(a) Disconnect the injector driver (EDU) connector.





(b) Disconnect the fuel pump 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):





Text in Illustration





(d) Reconnect the injector driver (EDU) connector.

(e) Reconnect the fuel pump for high pressure connector.

NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- Continue to next step.

3. CHECK HARNESS AND CONNECTOR (INJECTOR DRIVER - ECM)

(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):





Text in Illustration





(d) Reconnect the ECM connector.

(e) Reconnect the injector driver (EDU) connector.

NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- Continue to next step.

4. INSPECT ECM (FPD AND FPF1 VOLTAGE)

(a) Start the engine, and check the waveforms between terminals FPF1 and E1, and FPD and E1 of the E6 and E4 ECM connectors.





HINT
The correct waveform is as shown in the illustration.





(b) When the waveform of terminal FPF1 is the same as NG waveform 1, stop the engine, disconnect the E26 injector driver connector, and then turn the engine switch on (IG) and check for a change in the FPF1 waveform.





Result





B -- REPLACE INJECTOR DRIVER Removal

A -- REPLACE ECM Removal