Code No. P0173: Abnormal Fuel System (cylinder 2, 3) <Vehicles for Hong kong>

OPERATION

Refer to Code No. P0202 No. 2 Injector System .

Refer to Code No. P0203 No. 3 Injector System .

FUNCTION

If the fuel system goes out of order, the fuel correction valve will become larger.

The engine-A/T-ECU checks whether the fuel trim value is within a specified range.

TROUBLE JUDGMENT

Check Condition

In learning the air-fuel ratio.

Judgment Criteria

Long-term fuel trim has continued to be +12.5% or higher for 10 seconds.

Long-term fuel trim has continued to be -12.5% or higher for 10 seconds.

PROBABLE CAUSE

Failed intake air temperature sensor

Failed air flow sensor

Failed purge control solenoid valve

Failed injector

Air drawn in from gaps in gasket, seals, etc.

Failed engine coolant temperature sensor

Failed manifold absolute pressure sensor

Failed barometric pressure sensor

Exhaust leak

Incorrect fuel pressure

Failed engine-A/T-ECU

DIAGNOSIS PROCEDURE

STEP 1. MUT-II/III diagnosis code

Q: Is any other diagnosis code than P0173 output?

YES: Inspection chart for diagnosis code (Refer to

).
NO: Go to Step 2

STEP 2. MUT-II/III data list

Refer to Data List Reference Table .

Item 12: Air flow sensor

Item 13: Intake air temperature sensor

Item 21: Engine coolant temperature sensor

Item 95: Manifold absolute sensor

Q: Are the check results normal?

YES: Go to Step 3

.
NO: Perform the diagnosis code classified check procedure for the sensor that has shown an abnormal data value (Refer to Inspection Chart for Diagnosis Code

STEP 3: MUT-II/III data list

Refer to Data List Reference Table .

Item 25: Barometric pressure sensor

Q: Are the check results normal?

YES: Go to Step 4

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

STEP 4. Check throttle body (throttle valve portion) for contamination.

Q: Is the check result normal?

YES: Go to Step 5

.
NO: Clean throttle body (throttle valve portion) (Refer to

STEP 5. Check for intake of air from intake hose and inlet manifold.

Q: Is the check result normal?

YES: Go to Step 6

.
NO: Repair.

STEP 6. Check for leakage of exhaust emission from exhaust manifold.

Q: Is the check result normal?

YES: Go to Step 7

.
NO: Repair.

STEP 7. Connector Check: Injector connector

B-02 (No. 2 injector connector).

B-04 (No. 3 injector connector).

Q: Are the check results normal?

YES: Go to Step 8

.
NO: Replace.

STEP 8. Check injector itself.

Check Injector itself (Refer to ).

Q: Is the check result normal?

YES: Go to Step 9

.
NO: Replace injector.

STEP 9. Connector check: B-17X engine control relay connector and C-134 engine-A/T-ECU connector

Q: Is the check result normal?

YES: Go to Step 10

.
NO: Repair.

STEP 10. Check harness between B-17X engine control relay connector and injector connector.

Check harness between B-17X (terminal No. 1) engine control relay connector and B-02 (terminal No. 1) No. 2 injector connector.

Check harness between B-17X (terminal No. 1) engine control relay connector and B-04 (terminal No. 1) No. 3 injector connector.

Check power supply line for damage.

Q: Are the check results normal?

YES: Go to Step 11

.
NO: Repair.

STEP 11. Check harness between injector connector and C-134 engine-A/T-ECU connector.

Check harness between B-02 (terminal No. 2) No. 2 injector connector and C-134 (terminal No. 5) engine-A/T-ECU connector.

Check harness between B-04 (terminal No. 2) No. 3 injector connector and C-134 (terminal No. 14) engine-A/T-ECU connector.

Q: Are the check results normal?

YES: Go to Step 12

.
NO: Repair.

STEP 12. Check purge control solenoid valve itself.

Check purge control solenoid valve itself (Refer to GROUP 17 - Emission Control System - Evaporative Emission Control System - Purge Control Solenoid Valve ).

Q: Is the check result normal?

YES: Go to Step 13

.
NO: Replace purge control solenoid valve.

STEP 13. Fuel pressure measurement.

Fuel pressure measurement (Refer to ).

Q: Is the check result normal?

YES: Replace engine-A/T-ECU.
NO: Repair.


Code No. P0173: Abnormal Fuel System (cylinder 2, 3) <Vehicles for Hong kong>

OPERATION Refer to Code No. P0202 No. 2 Injector System . Refer to Code No. P0203 No. 3 Injector System .
FUNCTION If the fuel system goes out of order, the fuel correction valve will become larger. The engine-A/T-ECU checks whether the fuel trim value is within a specified range.
TROUBLE JUDGMENT Check Condition In learning the air-fuel ratio. Judgment Criteria Long-term fuel trim has continued to be +12.5% or higher for 10 seconds. or Long-term fuel trim has continued to be -12.5% or higher for 10 seconds.
PROBABLE CAUSE Failed intake air temperature sensor Failed air flow sensor Failed purge control solenoid valve Failed injector Air drawn in from gaps in gasket, seals, etc. Failed engine coolant temperature sensor Failed manifold absolute pressure sensor Failed barometric pressure sensor Exhaust leak Incorrect fuel pressure Failed engine-A/T-ECU
	DIAGNOSIS PROCEDURE

	STEP 1. MUT-II/III diagnosis code Q: Is any other diagnosis code than P0173 output? YES: Inspection chart for diagnosis code (Refer to ). NO: Go to Step 2 .
	STEP 2. MUT-II/III data list Refer to Data List Reference Table . Item 12: Air flow sensor Item 13: Intake air temperature sensor Item 21: Engine coolant temperature sensor Item 95: Manifold absolute sensor Q: Are the check results normal? YES: Go to Step 3 . NO: Perform the diagnosis code classified check procedure for the sensor that has shown an abnormal data value (Refer to Inspection Chart for Diagnosis Code ).
	STEP 3: MUT-II/III data list Refer to Data List Reference Table . Item 25: Barometric pressure sensor Q: Are the check results normal? YES: Go to Step 4 . NO: Replace engine-A/T-ECU.
	STEP 4. Check throttle body (throttle valve portion) for contamination. Q: Is the check result normal? YES: Go to Step 5 . NO: Clean throttle body (throttle valve portion) (Refer to ).
	STEP 5. Check for intake of air from intake hose and inlet manifold. Q: Is the check result normal? YES: Go to Step 6 . NO: Repair.
	STEP 6. Check for leakage of exhaust emission from exhaust manifold. Q: Is the check result normal? YES: Go to Step 7 . NO: Repair.
	STEP 7. Connector Check: Injector connector
	B-02 (No. 2 injector connector). B-04 (No. 3 injector connector). Q: Are the check results normal? YES: Go to Step 8 . NO: Replace.
	STEP 8. Check injector itself. Check Injector itself (Refer to ). Q: Is the check result normal? YES: Go to Step 9 . NO: Replace injector.
	STEP 9. Connector check: B-17X engine control relay connector and C-134 engine-A/T-ECU connector
	Q: Is the check result normal? YES: Go to Step 10 . NO: Repair.
	STEP 10. Check harness between B-17X engine control relay connector and injector connector.
	Check harness between B-17X (terminal No. 1) engine control relay connector and B-02 (terminal No. 1) No. 2 injector connector. Check harness between B-17X (terminal No. 1) engine control relay connector and B-04 (terminal No. 1) No. 3 injector connector. Check power supply line for damage. Q: Are the check results normal? YES: Go to Step 11 . NO: Repair.
	STEP 11. Check harness between injector connector and C-134 engine-A/T-ECU connector.
	Check harness between B-02 (terminal No. 2) No. 2 injector connector and C-134 (terminal No. 5) engine-A/T-ECU connector. Check harness between B-04 (terminal No. 2) No. 3 injector connector and C-134 (terminal No. 14) engine-A/T-ECU connector. Q: Are the check results normal? YES: Go to Step 12 . NO: Repair.
	STEP 12. Check purge control solenoid valve itself. Check purge control solenoid valve itself (Refer to GROUP 17 - Emission Control System - Evaporative Emission Control System - Purge Control Solenoid Valve ). Q: Is the check result normal? YES: Go to Step 13 . NO: Replace purge control solenoid valve.
	STEP 13. Fuel pressure measurement. Fuel pressure measurement (Refer to ). Q: Is the check result normal? YES: Replace engine-A/T-ECU. NO: Repair.