Code No. P0201: No. 1 Injector System

OPERATION

Power is supplied to the injector (terminal No. 1) from the injector relay (terminal No. 3).
The engine-ECU (terminal No. 2) makes the power transistor in the unit be in ON position, and that makes currents go on the injector (terminal No. 2).

FUNCTION

The engine-ECU controls the power supply interval of the injector.
The fuel injection amount of the injector depends on the power supply interval.

TROUBLE JUDGMENT

Check Condition

Engine is running.

Judgement Criterion

The supply voltage is less than 3 V without the injector driving.

Check Condition

Engine is running.

Judgement Criterion

The coil current is more than 4.5 A with the injector driving.

PROBABLE CAUSES

Failed No. 1 injector
Open/short circuit or harness damage in No. 1 injector circuit or loose connector contact
Failed engine-ECU

DIAGNOSIS PROCEDURE

STEP 1. M.U.T.-III actuator test

Item 1: No. 1 injector

OK: Idling state varies.

Q. Is the check result normal?

	Intermittent malfunction (Refer to GROUP 00 - How to Use Troubleshooting/Inspection Service Points - How to Cope with Intermittent Malfunctions ).

	Go to Step 2 .

STEP 2. Connector check: B-101 No. 1 injector connector

Q. Is the check result normal?

	Go to Step 3 .

	Repair or replace the connector.

STEP 3. Check No. 1 injector itself.

Check No. 1 injector itself (Refer to ).

Q. Is the check result normal?

	Go to Step 4 .

	Replace the No. 1 injector.

STEP 4. Perform voltage measurement at B-101 No. 1 injector connector.

Disconnect connector, and measure at harness side.
Ignition switch: ON
Voltage between terminal No. 1 and earth.

OK: System voltage

Q. Is the check result normal?

	Go to Step 14 .

	Go to Step 5 .

STEP 5. Connector check: A-23X injector relay connector

Q. Is the check result normal?

	Go to Step 6 .

	Repair or replace the connector.

STEP 6. Check injector relay itself.

Check injector relay itself (Refer to ).

Q. Is the check result normal?

	Go to Step 7 .

	Replace the injector relay.

STEP 7. Perform resistance measurement at A-23X injector relay connector.

Remove relay and measure at connector side.
Resistance between terminal No. 2 and earth.

OK: Continuity (2 Ω or less)

Q. Is the check result normal?

	Go to Step 8 .

	Check and repair harness between A-23X (terminal No. 2) injector relay connector and body earth. Check earthing line for open circuit and damage.

STEP 8. Perform voltage measurement at A-23X injector relay connector.

Remove relay and measure at connector side.
Ignition switch: ON
Resistance between terminal No. 1 and earth.

OK: System voltage

Q. Is the check result normal?

	Go to Step 10 .

	Go to Step 9 .

STEP 9. Connector check: C-304 ETACS-ECU connector

Q. Is the check result normal?

	Check and repair harness between C-304 (terminal No. 10) ETACS-ECU connector and A-23X (terminal No. 1) injector relay connector. Check power supply line for open/short circuit.

	Repair or replace the connector.

STEP 10. Perform voltage measurement at A-23X injector relay connector.

Remove relay and measure at connector side.
Ignition switch: ON
Voltage between terminal No. 4 and earth.

OK: System voltage

Q. Is the check result normal?

	Go to Step 12 .

	Go to Step 11 .

STEP 11. Connector check: A-33X engine control relay connector

Q. Is the check result normal?

	Check and repair harness between A-33X (terminal No. 2) engine control relay connector and A-23X (terminal No. 4) injector relay connector. Check power supply line for open/short circuit.

	Repair or replace the connector.

STEP 12. Check harness between A-23X (terminal No. 3) injector relay connector and B-101 (terminal No. 1) No. 1 injector connector.

note

Before checking harness, check intermediate connector A-11, and repair if necessary.

Check power supply line for open/short circuit.

Q. Is the check result normal?

	Go to Step 13 .

	Repair the damaged harness wire.

STEP 13. Connector check: C-304 ETACS-ECU connector

Q. Is the check result normal?

	Check and repair harness between C-304 (terminal No. 10) ETACS-ECU connector and A-23X (terminal No. 1) injector relay connector. Check power supply line for damage.

	Repair or replace the connector.

STEP 14. Connector check: A-33X engine control relay connector and A-23X injector relay connector.

Q. Are the check results normal?

	Go to Step 15 .

	Repair or replace the connector.

STEP 15. Check harness between A-33X (terminal No. 2) engine control relay connector and A-23X (terminal No. 4) injector relay connector.

Check power supply line for damage.

Q. Is the check result normal?

	Go to Step 16 .

	Repair the damaged harness wire.

STEP 16. Check harness between A-23X (terminal No. 3) injector relay connector and B-101 (terminal No. 1) No. 1 injector connector.

note

Before checking harness, check intermediate connector A-11, and repair if necessary.

Check power supply line for damage.

Q. Is the check result normal?

	Go to Step 17 .

	Repair the damaged harness wire.

STEP 17. Connector check: B-08 engine-ECU connector

Q. Is the check result normal?

	Go to Step 18 .

	Repair or replace the connector.

STEP 18. Check harness between B-101 (terminal No. 2) No. 1 injector connector and B-08 (terminal No. 2) engine-ECU connector.

Check output line for open/short circuit and damage.

Q. Is the check result normal?

	Go to Step 19 .

	Repair the damaged harness wire.

STEP 19. Perform signal wave pattern measurement at B-08 engine-ECU connector (Using an oscilloscope).

Disconnect engine-ECU connector, and connect special tool power plant ECU check harness (MB992110) to measure at connector for inspection.
Engine: Idling
Transmission: Neutral <M/T> or P range <CVT>
Voltage between terminal No. 2 and earth.

OK: Waveforms should be displayed on inspection procedure using an oscilloscope (Refer to ).

Q. Is the check result normal?

	Intermittent malfunction (Refer to GROUP 00 - How to Use Troubleshooting/Inspection Service Points - How to Cope with Intermittent Malfunctions ).

	Replace the engine-ECU.