Inspection Procedure 34: Fuel Pressure Control Solenoid Valve System <DOHC>

CONDITION

Power is supplied from the engine control relay (terminal No. 1) to the fuel pressure control solenoid valve (terminal No. 1).

The engine-A/T-ECU (terminal No. 93) causes the power transistor in the unit to be ON to supply power to the fuel pressure control solenoid valve (terminal No. 2).

FUNCTION

In response to a signal from the engine-A/T-ECU, the fuel pressure control solenoid valve switches the pressure to be introduced into the fuel pressure regulator between the intake manifold negative pressure and atmospheric pressure.

PROBABLE CAUSE

Failed fuel pressure control solenoid valve

Open/short circuit in fuel pressure control solenoid valve circuit or loose connector contact

Failed engine-A/T-ECU

DIAGNOSIS PROCEDURE

STEP 1. MUT-II/III actuator test

Refer to Actuator test reference table list .

Item 09: Fuel pressure control solenoid valve

OK: Operating sound can be heard and the valve vibrates.

Q: Is the check result normal?

YES: Intermittent malfunction (Refer to GROUP 00 - How to Use Troubleshooting/Inspection Service Points)

.
NO: Go to Step 2

STEP 2. Connector check: B-114 fuel pressure control solenoid valve connector

Q: Is the check result normal?

YES: Go to Step 3

.
NO: Repair.

STEP 3. Perform resistance measurement at B-114 fuel pressure control solenoid valve connector.

Disconnect connector, and measure at solenoid valve side.

Resistance between terminal No. 1 and No. 2.

OK: 28 - 36 Ω (at 20°C)

Q: Is the check result normal?

YES: Go to Step 4

.
NO: Replace fuel pressure control solenoid valve.

STEP 4. Perform voltage measurement at B-114 fuel pressure control solenoid valve connector.

Disconnect connector, and measure at harness side.

Ignition switch: ON

Voltage between terminal No. 1 and earth.

OK: Battery voltage

Q: Is the check result normal?

YES: Go to Step 6

.
NO: Go to Step 5

STEP 5. Connector check: B-17X engine control relay connector

Q: Is the check result normal?

YES:

Check intermediate connector C-17, and repair if necessary. If intermediate connector is normal, check and repair harness between B-114 (terminal No. 2) fuel pressure control solenoid valve connector and B-17X (terminal No. 1) engine control relay connector.

Check power supply line for open/short circuit.

NO: Repair.

STEP 6. Perform voltage measurement at C-110 engine-A/T-ECU connector.

Disconnect connector, and measure at harness side.

Ignition switch: ON

Voltage between terminal No. 93 and earth.

OK: Battery voltage

Q: Is the check result normal?

YES: Go to Step 8

.
NO: Go to Step 7

STEP 7. Connector check: C-110 engine-A/T-ECU connector

Q: Is the check result normal?

YES:

Check and repair harness between B-114 (terminal No. 2) fuel pressure control solenoid valve connector and C-110 (terminal No. 93) engine-A/T-ECU connector.

Check output line for open/short circuit.

NO: Repair.

STEP 8. Connector check: C-110 engine-A/T-ECU connector

Q: Is the check result normal?

YES: Go to Step 9

.
NO: Repair.

STEP 9. Check harness between B-114 (terminal No. 2) fuel pressure control solenoid valve connector and C-110 (terminal No. 93) engine-A/T-ECU connector.

Check output line for damage.

Q: Is the check result normal?

YES: Go to Step 10

.
NO: Repair.

STEP 10. Check harness between B-114 (terminal No. 1) fuel pressure control solenoid valve connector and B-17X (terminal No. 1) engine control relay connector.

NOTE: Before checking harness, check intermediate connector C-17, and repair if necessary.

Check power supply line for damage.

Q: Is the check result normal?

YES: Go to Step 11

.
NO: Repair.

STEP 11. MUT-II/III actuator test

Refer to Actuator reference table list .

Item 09: Fuel pressure control solenoid valve

OK: Operating sound can be heard and the valve vibrates.

Q: Is the check result normal?

YES: Intermittent malfunction (Refer to GROUP 00 - How to Use Troubleshooting/Inspection Service Points

).
NO: Replace engine-A/T-ECU.


Inspection Procedure 34: Fuel Pressure Control Solenoid Valve System <DOHC>

CONDITION Power is supplied from the engine control relay (terminal No. 1) to the fuel pressure control solenoid valve (terminal No. 1). The engine-A/T-ECU (terminal No. 93) causes the power transistor in the unit to be ON to supply power to the fuel pressure control solenoid valve (terminal No. 2).
FUNCTION In response to a signal from the engine-A/T-ECU, the fuel pressure control solenoid valve switches the pressure to be introduced into the fuel pressure regulator between the intake manifold negative pressure and atmospheric pressure.
PROBABLE CAUSE Failed fuel pressure control solenoid valve Open/short circuit in fuel pressure control solenoid valve circuit or loose connector contact Failed engine-A/T-ECU
	DIAGNOSIS PROCEDURE

	STEP 1. MUT-II/III actuator test Refer to Actuator test reference table list . Item 09: Fuel pressure control solenoid valve OK: Operating sound can be heard and the valve vibrates. Q: Is the check result normal? YES: Intermittent malfunction (Refer to GROUP 00 - How to Use Troubleshooting/Inspection Service Points) . NO: Go to Step 2 .
	STEP 2. Connector check: B-114 fuel pressure control solenoid valve connector
	Q: Is the check result normal? YES: Go to Step 3 . NO: Repair.
	STEP 3. Perform resistance measurement at B-114 fuel pressure control solenoid valve connector.
	Disconnect connector, and measure at solenoid valve side. Resistance between terminal No. 1 and No. 2. OK: 28 - 36 Ω (at 20°C) Q: Is the check result normal? YES: Go to Step 4 . NO: Replace fuel pressure control solenoid valve.
	STEP 4. Perform voltage measurement at B-114 fuel pressure control solenoid valve connector.
	Disconnect connector, and measure at harness side. Ignition switch: ON Voltage between terminal No. 1 and earth. OK: Battery voltage Q: Is the check result normal? YES: Go to Step 6 . NO: Go to Step 5 .
	STEP 5. Connector check: B-17X engine control relay connector
	Q: Is the check result normal? YES: Check intermediate connector C-17, and repair if necessary. If intermediate connector is normal, check and repair harness between B-114 (terminal No. 2) fuel pressure control solenoid valve connector and B-17X (terminal No. 1) engine control relay connector. Check power supply line for open/short circuit. NO: Repair.
	STEP 6. Perform voltage measurement at C-110 engine-A/T-ECU connector.
	Disconnect connector, and measure at harness side. Ignition switch: ON Voltage between terminal No. 93 and earth. OK: Battery voltage Q: Is the check result normal? YES: Go to Step 8 . NO: Go to Step 7 .
	STEP 7. Connector check: C-110 engine-A/T-ECU connector
	Q: Is the check result normal? YES: Check and repair harness between B-114 (terminal No. 2) fuel pressure control solenoid valve connector and C-110 (terminal No. 93) engine-A/T-ECU connector. Check output line for open/short circuit. NO: Repair.
	STEP 8. Connector check: C-110 engine-A/T-ECU connector
	Q: Is the check result normal? YES: Go to Step 9 . NO: Repair.
	STEP 9. Check harness between B-114 (terminal No. 2) fuel pressure control solenoid valve connector and C-110 (terminal No. 93) engine-A/T-ECU connector.
	Check output line for damage. Q: Is the check result normal? YES: Go to Step 10 . NO: Repair.
	STEP 10. Check harness between B-114 (terminal No. 1) fuel pressure control solenoid valve connector and B-17X (terminal No. 1) engine control relay connector.
	NOTE: Before checking harness, check intermediate connector C-17, and repair if necessary. Check power supply line for damage. Q: Is the check result normal? YES: Go to Step 11 . NO: Repair.
	STEP 11. MUT-II/III actuator test Refer to Actuator reference table list . Item 09: Fuel pressure control solenoid valve OK: Operating sound can be heard and the valve vibrates. Q: Is the check result normal? YES: Intermittent malfunction (Refer to GROUP 00 - How to Use Troubleshooting/Inspection Service Points ). NO: Replace engine-A/T-ECU.