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P0090

DTC P0090: Fuel Pressure Solenoid Circuit

Fuel Pressure Solenoid Circuit Part 1:




Fuel Pressure Solenoid Circuit Part 2:






CIRCUIT OPERATION
- The fuel pressure solenoid power is supplied from the MFI relay (terminal No.4).
- The ECM controls the fuel pressure solenoid ground by turning the power transistor in the ECM "ON" and "OFF".

TECHNICAL DESCRIPTION
- To judge if there is open circuit in the fuel pressure solenoid drive circuit, ECM measures the surge voltage of the fuel pressure solenoid coil.
- The ECM drives the fuel pressure solenoid. After the solenoid is turned off, the ECM will check if the solenoid coil produces a surge voltage of 2 volts or more.

DESCRIPTIONS OF MONITOR METHODS
- If a surge current is not generated in the coil after the fuel pressure solenoid has been actuated, an open circuit is determined to have occurred.

MONITOR EXECUTION
- Continuous

MONITOR EXECUTION CONDITIONS (Other monitor and Sensor)

Other Monitor (There is no temporary DTC stored in memory for the item monitored below)
- Not applicable

Sensor (The sensor below is determined to be normal)
- Not applicable

DTC SET CONDITIONS

Logic Flow Chart:




Logic Flow Chart

Check Conditions
- Engine is being cranked.
- Battery positive voltage is at between 10 and 16.5 volts.

Judgment Criteria
- The fuel pressure solenoid coil surge voltage (battery positive voltage +2 volts) is not detected for 0.2 second.
- The ECM monitors for this condition once during the drive cycle.

Check Conditions
- Battery positive voltage is at between 10 and 16.5 volts.
- Fuel pressure solenoid is ON.
- ON duty cycle of the turbocharger wastegate solenoid is 0 percent.
- More than 1 second has elapsed after the above mentioned conditions have been met.

Judgment Criterion
- The fuel pressure solenoid coil surge voltage (battery positive voltage +2 volts) is not detected for 1 second. When the fuel pressure solenoid is turned OFF.

OBD-II DRIVE CYCLE PATTERN
Refer to Diagnostic Function - OBD-II Drive Cycle - Pattern 23. OBD-II Drive Cycle Pattern Lists

TROUBLESHOOTING HINTS (The most likely causes for this code to be set are:)
- Fuel pressure solenoid failed.
- Open or shorted fuel pressure solenoid circuit, harness damage, or connector damage.
- ECM failed.

DIAGNOSIS

Required Special Tools:
- MB991958: Scan Tool (M.U.T.-III Sub Assembly)
- MB991824: V.C.I.
- MB991827: USB Cable
- MB991911: Main Harness B

STEP 1. Using scan tool MB991958, check actuator test item 13: fuel pressure solenoid.

CAUTION: To prevent damage to scan tool MB991958, always turn the ignition switch to the "LOCK" (OFF) position before connecting or disconnecting scan tool MB991958.




1. Connect scan tool MB991958 to the data link connector.
2. Turn the ignition switch to the "ON" position.
3. Set scan tool MB991958 to the actuator test mode for item 12, fuel pressure solenoid.
- An operation sound should be heard and vibration should be felt when the fuel pressure solenoid is operated.

4. Turn the ignition switch to the "LOCK" (OFF) position.

Q: Is the solenoid operating properly?

YES: It can be assumed that this malfunction is intermittent.

NO: Go to Step 2.




STEP 2. Check harness connector B-28 at the fuel pressure solenoid for damage.

Q: Is the harness connector in good condition?

YES: Go to Step 3.

NO: Repair or replace it. Then go to Step 12.

STEP 3 Check the fuel pressure solenoid.




1. Disconnect the fuel pressure solenoid connector B-28.




2. Measure the resistance between fuel pressure solenoid side connector terminal No.1 and No.2.

Standard value: 29 - 35 Ohms [at 20 degrees C (68 degrees F)]

Q: Is the measured resistance between 29 and 35 Ohms [at 20 degrees C (68 degrees F)]?

YES: Go to Step 4.

NO: Replace the fuel pressure solenoid. Then go to Step 12.

STEP 4. Measure the power supply voltage at fuel pressure solenoid harness side connector B-28.




1. Disconnect connector B-28 and measure at the harness side.
2. Turn the ignition switch to the "ON" position.




3. Measure the voltage between terminal No.1 and ground.
- Voltage should be battery positive voltage.

4. Turn the ignition switch to the "LOCK" (OFF) position.

Q: Is battery positive voltage (approximately 12 volts) present?

YES: Go to Step 6.

NO: Go to Step 5.




STEP 5. Check harness connector B-12X at MFI relay for damage.

Q: Is the harness connector in good condition?

YES: Repair harness wire between MFI relay connector B-12X (terminal No.4) and fuel pressure solenoid connector B-28 (terminal No.1) because of open circuit or short circuit to ground. Then go to Step 12.

NO: Repair or replace it. Then go to Step 12.

STEP 6. Measure the power supply voltage at ECM connector C-119 by backprobing.




1. Do not disconnect connector C-119.
2. Turn the ignition switch to the "ON" position.




3. Measure the voltage between terminal No.48 and ground by backprobing.
- Voltage should be battery positive voltage.

4. Turn the ignition switch to the "LOCK" (OFF) position.

Q: Is battery positive voltage (approximately 12 volts) present?

YES: Go to Step 9.

NO: Go to Step 7.




STEP 7. Check harness connector C-119 at ECM for damage.

Q: Is the harness connector in good condition?

YES: Go to Step 8.

NO: Repair or replace it. Then go to Step 12.







STEP 8. Check for open circuit and short circuit to ground between fuel pressure solenoid connector B-28 (terminal No.2) and ECM connector C-119 (terminal No.48).

Q: Is the harness wire in good condition?

YES: Replace the ECM. Then go to Step 12.

NO: Repair it. Then go to Step 12.




STEP 9. Check harness connector C-119 at ECM for damage.

Q: Is the harness connector in good condition?

YES: Go to Step 10.

NO: Repair or replace it. Then go to Step 12.







STEP 10. Check for harness damage between MFI relay connector B-12X (terminal No.4) and fuel pressure solenoid connector B-28 (terminal No.1).

Q: Is the harness wire in good condition?

YES: Go to Step 11.

NO: Repair it. Then go to Step 12.







STEP 11. Check for harness damage between fuel pressure solenoid connector B-28 (terminal No.2) and ECM connector C-119 (terminal No.48).

Q: Is the harness wire in good condition?

YES: Replace the ECM. Then go to Step 12.

NO: Repair it. Then go to Step 12.

STEP 12. Test the OBD-II drive cycle.

1. Carry out a test drive with the drive cycle pattern. Refer to, Diagnostic Function - OBD-II Drive Cycle - Pattern 23. OBD-II Drive Cycle Pattern Lists
2. Check the diagnostic trouble code (DTC).

Q: Is DTC P0090 set?

YES: Retry the troubleshooting.

NO: The inspection is complete.