P001A

DTC P001A: Camshaft Profile Control (engine oil control valve) Circuit


















CIRCUIT OPERATION

- The engine oil control valve power is supplied from the MFI relay (terminal No. 4).
- The ECM[ M/T] or the PCM[ A/T] controls ground engine oil control valve by turning the power transistor in the ECM[ M/T] or the PCM[ A/T] "ON" and "OFF".

TECHNICAL DESCRIPTION

- The engine oil control valve switches the cams to operate the MIVEC system in the low-speed or high-speed mode in accordance with the signals from the ECM[ M/T] or the PCM[ A/T].

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






Check Conditions

- Ignition switch: "ON"
- Engine oil control valve is "OFF"
- Battery positive voltage is between10 and 16.5 volts.
- 0.1 second has elapsed after the above mentions have been met.
Judgement Criterion

- The ECM[ M/T] or the PCM[ A/T] terminal voltage of engine 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 23 Monitors, Trips, Drive Cycles and Readiness Codes .

TROUBLESHOOTING HINTS (The most likely causes for this code to be set are:)

- Engine oil control valve failed.
- Open or shorted engine oil control valve circuit, or harness damage or connector damage.
- ECM failed.[ M/T]
- PCM failed.[ A/T]

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-32 at the engine oil control valve for damage.





Q. Is the harness connector in good condition?

YES Go to Step 2.

NO Repair or replace it. Harness Connector Inspection.
Then go to Step 12.

STEP 2. Check the engine oil control valve.





(1)Disconnect the engine oil control valve connector B-32.





(2)Measure the resistance between engine oil control valve side connector terminal No. 1 and No. 2.
Standard value: 6.9 - 7.9ohms [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 engine oil control valve. Then go to Step 12.

STEP 3. Measure the power supply voltage at engine oil control valve harness side connector B-32.





(1)Disconnect the connector B-32 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 engine oil control valve connector B-32 (terminal No. 1) because of open circuit or short circuit to ground. Then go to Step 12.

NO Repair or replace it. Harness Connector Inspection.
Then go to Step 12.

STEP 5. Measure the power supply voltage at ECM [M/T] or PCM [A/T] connector B-22 by using power plant ECU check harness special tool MB991923.









(1)Disconnect all ECM [M/T] connectors or PCM [A/T] 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. 128 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 [M/T] or PCM [A/T] for damage.





Q. Is the harness connector in good condition?

YES Go to Step 7.

NO Repair or replace it. Harness Connector Inspection.
Then go to Step 12.

STEP 7. Check for open circuit and short circuit to ground between engine oil control valve connector B-32 (terminal No. 2) and ECM [M/T] or PCM [A/T] connector B-22 (terminal No. 128).









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. Encrypted Code Registration Criteria Table.
Then go to Step 12.

NO Repair it. Then go to Step 12.

STEP 8. Check harness connector B-22 at ECM [M/T] or PCM [A/T] for damage.





Q. Is the harness connector in good condition?

YES Go to Step 9.

NO Repair or replace it. Harness Connector Inspection.
Then go to Step 12.

STEP 9. Check for harness damage between MFI relay connector B-16X
(terminal No. 4) and engine oil control valve connector B-32 (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 engine oil control valve connector B-32 (terminal No. 2) and ECM [M/T] or PCM [A/T] connector B-22 (terminal No. 128).









Q. Is the harness wire in good condition?

YES Go to Step 11.

NO Repair it. Then go to Step 12.

STEP 11.Check the trouble symptoms.

(1)Carry out test drive with the drive cycle pattern. Refer to Diagnostic Function - OBD-II Drive Cycle - Pattern 23 Monitors, Trips, Drive Cycles and Readiness Codes.

(2)Check the diagnostic trouble code (DTC).

Q. Is DTC P001A set?

YES Replace the ECM or the PCM. When the ECM or the PCM is replaced, register the encrypted code. Encrypted Code Registration Criteria Table.
Then go to Step 12.
NO It can be assumed that this malfunction is intermittent. How to Cope With Intermittent Malfunctions.
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 Monitors, Trips, Drive Cycles and Readiness Codes.

(2)Check the diagnostic trouble code (DTC).

Q. Is DTC P001A set?

YES Retry the troubleshooting.
NO The inspection is complete.