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P1021

DTC P1021: Engine Oil Control Valve Circuit (bank 1)

Right Bank Engine Oil Control Valve Circuit Part 1:




Right Bank Engine Oil Control Valve Circuit Part 2:






CIRCUIT OPERATION
- The right bank engine oil control valve power is supplied from the MFI relay (terminal No. 4).
- The ECM or the PCM controls ground right bank engine oil control valve by turning the power transistor in the ECM or the PCM "ON" and "OFF".

TECHNICAL DESCRIPTION
- The right bank engine oil pressure switch the cams to operate the MIVEC system in the low- speed or high- speed mode in accordance with the signals from the ECM or the PCM
.

DESCRIPTIONS OF MONITOR METHODS
Circuit voltage stays low when solenoid status is off.

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
- Ignition switch: "ON"
- Right bank engine oil control valve is OFF.
- Battery positive voltage is between 10 and 16.5 volts.
- 0.1 seconds has elapsed after the above mentioned conditions have been met.

Judgment Criterion
- The ECM or PCM
terminal voltage of right bank engine oil control valve circuit is less than 1.5 volts for 2 seconds.

OBD-II Drive Cycle PATTERN
Refer to Diagnostic Function - OBD-II Drive Cycle - Pattern 22.
OBD-II Drive Cycle

TROUBLESHOOTING HINTS (The most likely causes for this code to be set are:)
- Right bank engine oil control valve failed.
- Open or shorted right bank engine oil control valve circuit, or harness damage or connector damage.
- ECM failed.
- PCM failed.

DIAGNOSIS

Required Special Tools:
- MB991958: Scan Tool (M.U.T.- III Sub Assembly)
- MB991824: V.C.I.
- MB991827: USB Cable
- MB991910: Main Harness A
- MB991923: Power Plant ECU Check Harness




STEP 1. Check harness connector B-107 at the right bank engine oil control valve for damage.

Q: Is the harness connector in good condition?

YES: Go to Step 2.

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

STEP 2. Check the right bank engine oil control valve.




1. Disconnect the engine oil control valve connector B-107.




2. Measure the resistance between engine oil control valve side connector terminal No. 1 and No. 2.

Standard value: 6.9 - 7.9 Ohms [at 20 °C (68 °F)]

Q: Is the measured resistance between 6.9 and 7.9 Ohms [at 20 °C (68 °F)]?

YES: Go to Step 3.

NO: Replace the right bank engine oil control valve. Then go to Step 12.

STEP 3. Measure the power supply voltage at right bank engine oil control valve harness side connector B-107.




1. Disconnect the connector B-107 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 5.

NO: Go to Step 4.




STEP 4. Check harness connector B-16X at MFI relay for damage.

Q: Is the harness connector in good condition?

YES: Repair harness wire between MFI relay connector B-16X (terminal No. 4) and right bank engine oil control valve connector B-107 (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 5. Measure the power supply voltage at ECM or PCM
connector B-22 by using power plant ECU check harness special tool MB991923.







1. Disconnect all ECM connectors or PCM
connectors. Connect the power plant ECU check harness special tool MB991923 between the separated connectors.
2. Turn the ignition switch to the "ON" position.




3. Measure the voltage between terminal No. 135 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 8.

NO: Go to Step 6.




STEP 6. Check harness connector B-22 at ECM or PCM
for damage.

Q: Is the harness connector in good condition?

YES: Go to Step 7.

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







STEP 7. Check for open circuit and short circuit to ground between right bank engine oil control valve connector B-107 (terminal No. 2) and ECM or PCM
connector B-22 (terminal No. 135).

Q: Is the harness wire in good condition?

YES: Replace the ECM or the PCM. When the ECM or the PCM is replaced, register the encrypted code. Then go to Step 12.

NO: Repair it. Then go to Step 12.




STEP 8. Check harness connector B-22 at ECM or PCM
for damage.

Q: Is the harness connector in good condition?

YES: Go to Step 9.

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







STEP 9. Check for harness damage between MFI relay connector B-16X (terminal No. 4) and right bank engine oil control valve connector B-107 (terminal No. 1).

Q: Is the harness wire in good condition?

YES: Go to Step 10.

NO: Repair it. Then go to Step 12.







STEP 10. Check for harness damage between right bank engine oil control valve connector B-107 (terminal No. 2) and ECM or PCM
connector B-22 (terminal No. 135).

Q: Is the harness wire in good condition?

YES: Go to Step 11.

NO: Repair it. Then go to Step 12.




STEP 11. Test the OBD-II Drive Cycle.

1. Carry out test drive with the drive cycle pattern. Refer to Diagnostic Function - OBD-II Drive Cycle - Pattern 19.
OBD-II Drive Cycle
2. Check the diagnostic trouble code (DTC).

Q: Is DTC P1021 set?

YES: Replace the ECM or the PCM. When the ECM or the PCM is replaced, register the encrypted code. Then go to Step 12.

NO: It can be assumed that this malfunction is intermittent. Refer to How to Use Troubleshooting/Inspection Service Points - How to Cope with Intermittent Malfunctions.




STEP 12. Test the OBD-II Drive Cycle.

1. Carry out test drive with the drive cycle pattern. Refer to Diagnostic Function - OBD-II Drive Cycle - Pattern 19. OBD-II Drive Cycle
2. Check the diagnostic trouble code (DTC).

Q: Is DTC P1021 set?

YES: Retry the troubleshooting.

NO: The inspection is complete.